Vault Of Euclid

Today's setFriday, 7 August 2026

10 problems across Real & complex analysis, Calculus and Linear algebra.

22
Days
220
Problems served
1 hard Sequences Real & complex analysis
Determine whether \( \sum_{n=1}^{\infty} (-1)^{n+1} \frac{\sin (\pi/n)}{n^2} \) converges.
absolute-convergencealternating-seriescalculus-iicomparison-testdirect-comparison-testevaluate-convergenceinfinite-seriesp-seriesseries-convergencesinetrigonometric-functions

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2 core Antiderivatives Calculus
Evaluate \( \int \sec^2 4x \tan 4x \, dx \).
indefinite-integralintegration-by-substitutiontrigonometric-integralsecanttangentchain-rulepower-ruleevaluate-integralcalculus-iantiderivative

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3 hard The definite integral Calculus
Evaluate \(\lim_{n\to\infty} \frac{1}{n} \left( \sin \frac{\pi}{n} + \sin \frac{2\pi}{n} + \dots + \sin \frac{n\pi}{n} \right)\).
calculus-idefinite-integralriemann-sumlimit-of-a-sequencetrigonometric-functionsevaluate-limitintegrationfundamental-theorem-of-calculussine

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4 hard Differential equations Calculus
Use (8.4.12) to find \[ \mathcal{L}^{-1}\left(\frac{e^{-2s}}{s^2}\right). \]
inverse-laplace-transformsecond-shifting-theoremheaviside-step-functiontime-delayexponential-factorrational-functiondifferential-equationscalculusevaluate-inverse-transformlaplace-transform-propertiess-domaint-domain

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5 core Limits Calculus
\(\lim_{x\to 0} \frac{e^x}{x^2}\)
evaluate-limitinfinite-limitexponential-functionl-hopital-trapcalculus-ilimitsnon-indeterminate-formone-sided-limits

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6 core Parametric equations and vector functions Calculus
Find the distance traveled by a particle with position \((x, y)\) as \(t\) varies in the given time interval: \(x = \sin^2 t, y = \cos^2 t, 0 \le t \le 3\pi\).
parametric-equationsarc-lengthdistance-traveledtrigonometric-functionsabsolute-valuedefinite-integralchain-ruleperiodicitycalculus-iiintegrationdouble-angle-identityspeed

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7 core Logarithmic and exponential functions Calculus
Evaluate \( \lim_{x\to 0} \frac{\ln (1+x)}{x} \).
limitderivative-definitionnatural-logarithmindeterminate-formevaluate-limitcalculus-itranscendental-functionslimits-of-functions

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8 warmup Trigonometric and inverse trigonometric functions Calculus
Find \( \frac{d}{dx}(\sqrt{\sin x}) \).
derivativechain-rulesquare-rootsinetrigonometric-functionscalculus-ievaluate-derivativepower-rulecomposite-function

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9 core Linear transformations Linear algebra
Let $F$ and $G$ be the linear operators on $\mathbb{R}^2$ defined by $F(x,y) = (y,x)$ and $G(x,y) = (0,x)$. Find formulas defining the following operators: (a) $F + G$, (b) $2F - 3G$, (c) $FG$, (d) $GF$, (e) $F^2$, (f) $G^2$.

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10 core Vector spaces Linear algebra
Find an equation of the plane containing the lines $L_1$ and $L_2$: \[ L_1: x = -y = z \] \[ L_2: \frac{x-3}{2} = y = z - 2 \]
analytic-geometrycross-productdirection-vectorintersecting-lineslinear-algebramultivariable-calculusnormal-vectorparametric-equationsplane-equationsymmetric-equationsthree-dimensional-geometryvector-geometry

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