FAC1004: Rapid-Fire Drill Pack — Hyperbolic Differentiation & Integration
Objective: Achieve mechanical fluency in differentiating and integrating hyperbolic functions — pure pattern recognition and algebraic speed.
Target: 60–90 seconds per problem. If you stall >3 minutes, skip and mark it.
Total problems: 62
Estimated time: 1.5–2 hours (or two 45-minute sprints)
Cheat Sheet (Memorize First)
Exponential Definitions
$$\sinh x = \frac{e^x - e^{-x}}{2}, \quad \cosh x = \frac{e^x + e^{-x}}{2}, \quad \tanh x = \frac{\sinh x}{\cosh x}$$ $$\coth x = \frac{\cosh x}{\sinh x}, \quad \operatorname{sech} x = \frac{1}{\cosh x}, \quad \operatorname{csch} x = \frac{1}{\sinh x}$$
Fundamental Identity
$$\cosh^2 x - \sinh^2 x = 1, \quad 1 - \tanh^2 x = \operatorname{sech}^2 x, \quad \coth^2 x - 1 = \operatorname{csch}^2 x$$
Key Relations
$$\cosh x + \sinh x = e^x, \quad \cosh x - \sinh x = e^{-x}$$ $$\sinh(2x) = 2\sinh x \cosh x, \quad \cosh(2x) = \cosh^2 x + \sinh^2 x = 2\cosh^2 x - 1 = 2\sinh^2 x + 1$$
Derivatives
| Function | Derivative |
|---|---|
| $\sinh u$ | $\cosh u \cdot u'$ |
| $\cosh u$ | $\sinh u \cdot u'$ |
| $\tanh u$ | $\operatorname{sech}^2 u \cdot u'$ |
| $\coth u$ | $-\operatorname{csch}^2 u \cdot u'$ |
| $\operatorname{sech} u$ | $-\operatorname{sech} u \tanh u \cdot u'$ |
| $\operatorname{csch} u$ | $-\operatorname{csch} u \coth u \cdot u'$ |
Integrals
| Integral | Result |
|---|---|
| $\int \sinh u , du$ | $\cosh u + C$ |
| $\int \cosh u , du$ | $\sinh u + C$ |
| $\int \operatorname{sech}^2 u , du$ | $\tanh u + C$ |
| $\int \operatorname{csch}^2 u , du$ | $-\coth u + C$ |
| $\int \operatorname{sech} u \tanh u , du$ | $-\operatorname{sech} u + C$ |
| $\int \operatorname{csch} u \coth u , du$ | $-\operatorname{csch} u + C$ |
| $\int \tanh u , du$ | $\ln(\cosh u) + C$ |
| $\int \coth u , du$ | $\ln\vert\sinh u\vert + C$ |
Inverse Hyperbolic Integration Forms
| Integral | Result |
|---|---|
| $\displaystyle\int \frac{du}{\sqrt{a^2 + u^2}}$ | $\sinh^{-1}!\left(\frac{u}{a}\right) + C$ |
| $\displaystyle\int \frac{du}{\sqrt{u^2 - a^2}}$ | $\cosh^{-1}!\left(\frac{u}{a}\right) + C$ |
| $\displaystyle\int \frac{du}{a^2 - u^2}$ | $\frac{1}{a}\tanh^{-1}!\left(\frac{u}{a}\right) + C;;(\vert u\vert < a)\quad$ or $\quad\frac{1}{a}\coth^{-1}!\left(\frac{u}{a}\right) + C;;(\vert u\vert > a)$ |
| $\displaystyle\int \frac{du}{u\sqrt{a^2 + u^2}}$ | $-\frac{1}{a}\operatorname{csch}^{-1}!\left(\frac{u}{a}\right) + C$ |
| $\displaystyle\int \frac{du}{u\sqrt{a^2 - u^2}}$ | $-\frac{1}{a}\operatorname{sech}^{-1}!\left(\frac{u}{a}\right) + C$ |
Part A: Definitions, Identities & Basic Evaluation
Target: 60 seconds each. Pure recall and algebraic manipulation.
Set A1 — Evaluate & Simplify (8 problems)
- Express $\sinh(\ln 2)$ as a simplified fraction.
- Express $\cosh(\ln 3)$ as a simplified fraction.
- Simplify $\cosh^2 x - \sinh^2 x$ and state the identity.
- If $\sinh x = \frac{3}{4}$, find $\cosh x$ and $\tanh x$.
- If $\cosh x = \frac{5}{3}$ and $x > 0$, find $\sinh x$ and $\operatorname{sech} x$.
- Show that $\cosh x + \sinh x = e^x$ using exponential definitions.
- Simplify $e^{\sinh^{-1} x}$ in terms of $x$. (Hint: use the logarithmic form.)
- Show that $\sinh(2x) = 2\sinh x \cosh x$ using exponential definitions.
Score: ___/8
Set A2 — Identity Manipulation (6 problems)
- Prove $1 - \tanh^2 x = \operatorname{sech}^2 x$ starting from $\cosh^2 x - \sinh^2 x = 1$.
- If $\sinh x = t$, express $\cosh(2x)$ in terms of $t$.
- Simplify $\frac{\sinh x}{1 + \cosh x}$ into a single hyperbolic function.
- Solve for $x$: $2\cosh^2 x - 5\sinh x = 1$. (Hint: reduce to quadratic in $\sinh x$.)
- Show that $\ln(\cosh x + \sinh x) = x$.
- Prove $\coth^2 x - 1 = \operatorname{csch}^2 x$.
Score: ___/6
Part B: Derivatives of Hyperbolic Functions
Target: 60–90 seconds each. Apply derivative formula + chain rule.
Set B1 — Chain Rule Basics (8 problems)
Find $\frac{dy}{dx}$.
- $y = \sinh(3x + 2)$
- $y = \cosh(x^2)$
- $y = \tanh(5x)$
- $y = \coth(\sqrt{x})$
- $y = \operatorname{sech}(e^x)$
- $y = \operatorname{csch}(\ln x)$
- $y = \sinh(4x^3 - 2x)$
- $y = \cosh!\left(\frac{1}{x}\right)$
Score: ___/8
Set B2 — Composed & Nested Functions (8 problems)
Find $\frac{dy}{dx}$.
- $y = \ln(\cosh x)$
- $y = \sinh^3(2x)$
- $y = e^{\tanh x}$
- $y = \cosh(\sin x)$
- $y = \sinh(\ln x)$
- $y = \tanh^{-1}(\sinh x)$ (careful: chain rule on inverse tanh)
- $y = \sqrt{\cosh(2x)}$
- $y = \ln(\sinh(3x) + \cosh(3x))$ (simplify first using identity)
Score: ___/8
Set B3 — Product, Quotient & Implicit (8 problems)
Find $\frac{dy}{dx}$.
- $y = x^2 \sinh x$
- $y = \frac{\sinh x}{1 + \cosh x}$
- $y = e^x \tanh(2x)$
- $y = \frac{\cosh x}{x}$
- $y = \sinh x \cdot \cosh x$ (try two methods: product rule vs identity)
- $y = \ln!\left(\frac{\sinh x}{\cosh x}\right)$ (simplify first)
- $y = x \cosh x - \sinh x$
- $y = \coth(\ln x) \cdot \cos^{-1}(x^2)$
Score: ___/8
Part C: Integrals of Hyperbolic Functions
Target: 60–90 seconds each. Apply integral formula or $u$-substitution.
Set C1 — Direct Integrals (8 problems)
Evaluate.
- $\int \sinh(4x) , dx$
- $\int \cosh(2x - 1) , dx$
- $\int \operatorname{sech}^2(3x) , dx$
- $\int \operatorname{csch}^2!\left(\frac{x}{2}\right) , dx$
- $\int \tanh x , dx$ (Hint: write as $\frac{\sinh x}{\cosh x}$)
- $\int \coth x , dx$
- $\int \sinh x \cosh x , dx$ (try two methods)
- $\int \operatorname{sech} x \tanh x , dx$
Score: ___/8
Set C2 — $u$-Substitution (8 problems)
Evaluate.
- $\int \sinh^5 x \cosh x , dx$
- $\int \sqrt{\tanh x} \operatorname{sech}^2 x , dx$
- $\int x \sinh(x^2) , dx$
- $\int \coth^2 x \operatorname{csch}^2 x , dx$ (careful with sign from $du$)
- $\int \frac{\cosh x}{\sinh x} , dx$
- $\int \frac{\operatorname{sech}^2 x}{\tanh x} , dx$
- $\int \frac{\sinh x}{\sqrt{\cosh x}} , dx$
- $\int \cosh^3 x \sinh x , dx$
Score: ___/8
Set C3 — Definite Integrals (6 problems)
Evaluate.
- $\int_0^{\ln 2} \sinh x , dx$
- $\int_0^1 \cosh(2x) , dx$
- $\int_0^1 \frac{e^x - e^{-x}}{2} , dx$ (recognize the definition)
- $\int_0^1 \frac{dx}{\sqrt{1 + x^2}}$ (leads to $\sinh^{-1}$)
- $\int_0^{\ln 3} \tanh x , dx$
- $\int_{-1}^1 \sinh x , dx$ (use parity)
Score: ___/6
Part D: Integrals Leading to Inverse Hyperbolic Forms
Target: 90 seconds each. Recognize the standard form, perform $u$-substitution.
Set D1 — Standard Inverse Hyperbolic Integrals (8 problems)
Evaluate.
- $\int \frac{dx}{\sqrt{4 + x^2}}$
- $\int \frac{dx}{\sqrt{x^2 - 9}}$
- $\int \frac{dx}{25 - x^2}$ (specify domain: $\vert x\vert < 5$)
- $\int \frac{dx}{\sqrt{1 + 9x^2}}$
- $\int \frac{dx}{\sqrt{9x^2 - 16}}$
- $\int \frac{dx}{3 - 5x^2}$
- $\int \frac{dx}{x\sqrt{1 + x^2}}$
- $\int \frac{dx}{\sqrt{x^2 + 4x + 13}}$ (complete the square first)
Score: ___/8
Set D2 — Substitution Leading to Inverse Forms (6 problems)
Evaluate.
- $\int \frac{e^x}{\sqrt{e^{2x} + 1}} , dx$ (let $u = e^x$)
- $\int_0^{1/2} \frac{dx}{1 - 4x^2}$
- $\int \frac{dx}{\sqrt{(x+1)^2 + 4}}$
- $\int \frac{x}{\sqrt{x^4 - 1}} , dx$ (let $u = x^2$)
- $\int \frac{dx}{\sqrt{4x^2 + 12x + 5}}$ (factor inside root)
- $\int \frac{dx}{\sqrt{1 + e^{2x}}}$ (let $u = e^{-x}$)
Score: ___/6
Final Scorecard
| Part | Sets | Problems | Raw Score |
|---|---|---|---|
| A — Definitions & Identities | A1, A2 | 14 | ___/14 |
| B — Hyperbolic Derivatives | B1, B2, B3 | 24 | ___/24 |
| C — Hyperbolic Integrals | C1, C2, C3 | 22 | ___/22 |
| D — Inverse Hyperbolic Integrals | D1, D2 | 14 | ___/14 |
| TOTAL | 74 | ___/74 |
Proficiency Benchmarks
- 55/74 (74%) — Proficient. You can handle standard exam problems.
- 63/74 (85%) — Solid. Fast and accurate.
- 69/74 (93%) — Exam-ready. Any mistake is a careless slip.
Speed Benchmarks
- <1.5 hours: Excellent mechanical fluency. You own hyperbolic calculus.
- 1.5–2 hours: Good. Review missed patterns.
- >2 hours: Drill the specific sets you scored lowest on again tomorrow.
Error Log Template
After grading, list every wrong problem number with a one-word reason:
| Problem | Reason |
|---|---|
| e.g. 17 | sign error |
| e.g. 47 | forgot du factor |
Re-solve all wrong problems immediately with notes, then again in 24 hours without notes.
Answer Key
- $\sinh(\ln 2) = \frac{2 - 1/2}{2} = \frac{3}{4}$
- $\cosh(\ln 3) = \frac{3 + 1/3}{2} = \frac{5}{3}$
- $\cosh^2 x - \sinh^2 x = 1$
- $\cosh x = \frac{5}{4}$, $\tanh x = \frac{3}{5}$
- $\sinh x = \frac{4}{3}$, $\operatorname{sech} x = \frac{3}{5}$
- $\frac{e^x - e^{-x}}{2} + \frac{e^x + e^{-x}}{2} = e^x$
- $e^{\sinh^{-1} x} = x + \sqrt{1 + x^2}$
- $\frac{e^{2x} - e^{-2x}}{2} = 2 \cdot \frac{e^x - e^{-x}}{2} \cdot \frac{e^x + e^{-x}}{2} = 2\sinh x \cosh x$
- Divide $\cosh^2 x - \sinh^2 x = 1$ by $\cosh^2 x$
- $\cosh(2x) = 1 + 2\sinh^2 x = 1 + 2t^2$
- $\tanh(x/2)$
- $\sinh x = \frac{1}{2}$ or $-3$ (reject); $x = \sinh^{-1}(1/2)$
- $\ln(e^x) = x$
- Divide $\cosh^2 x - \sinh^2 x = 1$ by $\sinh^2 x$
- $3\cosh(3x+2)$
- $2x \sinh(x^2)$
- $5\operatorname{sech}^2(5x)$
- $-\frac{1}{2\sqrt{x}}\operatorname{csch}^2(\sqrt{x})$
- $-\operatorname{sech}(e^x) \tanh(e^x) \cdot e^x$
- $-\frac{1}{x}\operatorname{csch}(\ln x) \coth(\ln x)$
- $(12x^2 - 2)\cosh(4x^3 - 2x)$
- $-\frac{1}{x^2}\sinh(1/x)$
- $\tanh x$
- $3\sinh^2(2x) \cdot 2\cosh(2x) = 6\sinh^2(2x)\cosh(2x)$
- $e^{\tanh x} \operatorname{sech}^2 x$
- $-\sinh(\sin x) \cdot \cos x$
- $\frac{\cosh(\ln x)}{x} = \frac{x + 1/x}{2x} = \frac{x^2 + 1}{2x^2}$
- $\frac{\cosh x}{1 - \sinh^2 x} = \frac{\cosh x}{\cosh^2 x} = \operatorname{sech} x$
- $\frac{1}{2\sqrt{\cosh(2x)}} \cdot 2\sinh(2x) = \frac{\sinh(2x)}{\sqrt{\cosh(2x)}}$
- $\ln(e^{3x}) = 3x$, so derivative $= 3$
- $2x\sinh x + x^2\cosh x$
- $\frac{\cosh x(1 + \cosh x) - \sinh x(\sinh x)}{(1 + \cosh x)^2} = \frac{\cosh x + 1}{(1 + \cosh x)^2} = \frac{1}{1 + \cosh x}$
- $e^x\tanh(2x) + 2e^x \operatorname{sech}^2(2x)$
- $\frac{x\sinh x - \cosh x}{x^2}$
- $\sinh^2 x + \cosh^2 x = \cosh(2x)$, or $\frac{1}{2}\sinh(2x)$ derivative $= \cosh(2x)$
- $\ln(\tanh x)$, derivative $= \frac{\operatorname{sech}^2 x}{\tanh x} = \frac{1}{\sinh x \cosh x} = \operatorname{csch} x \operatorname{sech} x$
- $\cosh x + x\sinh x - \cosh x = x\sinh x$
- $-\frac{1}{x}\operatorname{csch}^2(\ln x) \cdot \cos^{-1}(x^2) - \frac{2x}{\sqrt{1-x^4}}\coth(\ln x)$
- $\frac{1}{4}\cosh(4x) + C$
- $\frac{1}{2}\sinh(2x-1) + C$
- $\frac{1}{3}\tanh(3x) + C$
- $-2\coth(x/2) + C$
- $\ln(\cosh x) + C$
- $\ln\vert\sinh x\vert + C$
- $\frac{1}{2}\sinh^2 x + C$ or $\frac{1}{2}\cosh^2 x + C$ (differ by constant)
- $-\operatorname{sech} x + C$
- $\frac{1}{6}\sinh^6 x + C$
- $\frac{2}{3}\tanh^{3/2} x + C$
- $\frac{1}{2}\cosh(x^2) + C$
- $-\frac{1}{3}\coth^3 x + C$
- $\ln\vert\sinh x\vert + C$
- $\ln\vert\tanh x\vert + C$
- $2\sqrt{\cosh x} + C$
- $\frac{1}{4}\cosh^4 x + C$
- $\cosh(\ln 2) - \cosh 0 = \frac{5}{3} - 1 = \frac{2}{3}$
- $\frac{1}{2}\sinh 2$
- $\int_0^1 \sinh x , dx = \cosh 1 - 1$
- $\sinh^{-1} 1 = \ln(1 + \sqrt{2})$
- $\ln(\cosh(\ln 3)) - \ln(\cosh 0) = \ln(5/3) - \ln 1 = \ln(5/3)$
- $0$ (odd function over symmetric interval)
- $\sinh^{-1}(x/2) + C$
- $\cosh^{-1}(x/3) + C$
- $\frac{1}{5}\tanh^{-1}(x/5) + C$
- $\frac{1}{3}\sinh^{-1}(3x) + C$
- $\frac{1}{3}\cosh^{-1}(3x/4) + C$
- $\frac{1}{\sqrt{5}}\tanh^{-1}!\left(\frac{\sqrt{5}x}{\sqrt{3}}\right) + C$ or $\frac{1}{2\sqrt{15}}\ln!\left\vert\frac{\sqrt{3} + \sqrt{5}x}{\sqrt{3} - \sqrt{5}x}\right\vert + C$
- $-\operatorname{csch}^{-1}(x) + C$ or $-\ln!\left\vert\frac{1 + \sqrt{1 + x^2}}{x}\right\vert + C$
- $\int \frac{dx}{\sqrt{(x+2)^2 + 9}} = \sinh^{-1}!\left(\frac{x+2}{3}\right) + C$
- $\sinh^{-1}(e^x) + C$
- $\frac{1}{2}\tanh^{-1}(2x)\big|_0^{1/2}$ diverges (approaches $\infty$ — improper)
- $\sinh^{-1}!\left(\frac{x+1}{2}\right) + C$
- $\frac{1}{2}\cosh^{-1}(x^2) + C$
- $\frac{1}{2}\cosh^{-1}!\left(\frac{x+3/2}{\sqrt{5}/2}\right) + C$
- $-\operatorname{csch}^{-1}(e^{x}) + C$ or $-\ln!\left(e^{-x} + \sqrt{1 + e^{-2x}}\right) + C$
Related Resources
- FAC1004 L17 — Hyperbolic Functions — introduction lecture
- FAC1004 L18 — Hyperbolic Functions (Derivatives & Integrals) — derivatives lecture
- FAC1004 L19-L20 — Inverse Hyperbolic Functions — inverse functions lecture
- FAC1004 L21-L22 — Integrals Involving Hyperbolic Functions — integrals lecture
- FAC1004 Tutorial 8 — Hyperbolic Functions — tutorial practice
- FAC1004 Tutorial 9 — Inverse Hyperbolic Functions — tutorial practice
- FAC1004 Tutorial 10 — Integration of Hyperbolic Functions — tutorial practice
- FAC1004 - Advanced Mathematics II (Computing) — course hub
- Hyperbolic Functions — concept page