Questions · Page 5 of 5

M.C.Q (1 Marks)

MCQ 2011 Mark
What is the value of $\int\limits_{-1}^{1} \sin^3\text{x}\cos^2\text{xdx:}$
  • $0$
  • B
    $1$
  • C
    $\frac{1}{2}$
  • D
    $2$
Answer
Correct option: A.
$0$
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MCQ 2021 Mark
Choose the correct answer in Exercise:
$\text{If}\ \text{f}(\text{x})=\int^{\text{x}}_{0}\text{t}\sin\text{t}\ \text{dt}$, then $\text{f}\text{(x)}$ is
  • A
    $\cos\text{x}+\text{x}\sin\text{x}$
  • $\text{x}\sin\text{x}$
  • C
    $\text{x}\cos\text{x}$
  • D
    $\sin\text{x}+\text{x}\cos\text{x}$
Answer
Correct option: B.
$\text{x}\sin\text{x}$
$\text{f}\text{(x)}=\int\limits_{0}^{\text{x}}\text{t}\sin\text{t}\ \text{dt}$

$\therefore\text{f}\text{'(x)}=\text{x}\sin\text{x}\ $ $\big[$$\therefore$ of first fundamental theorem$\big]$

$\text{f}\text{(x)}=\int\limits_{0}^{\text{x}}\text{t}\sin\text{t}\ \text{dt}$

$\therefore\text{f}\text{'(x)}=\text{x}\sin\text{x}\ \ $ $\big[$$\therefore$ of first fundamental theorem$\big]$
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MCQ 2031 Mark
Choose the correct answer in Exercise:
$\int^{\sqrt{3}}_{1}\frac{\text{dx}}{1+\text{x}^{2}}\text{equals}$
  • A
    $\frac{\pi}{3}$
  • $\frac{2\pi}{3}$
  • C
    $\frac{\pi}{6}$
  • D
    $\frac{\pi}{12}$
Answer
Correct option: B.
$\frac{2\pi}{3}$
$\int\frac{\text{dx}}{1+\text{x}^{2}}=\tan^{-1}\text{x}=\text{F}\text{(x)}$

By second fundamental theorem of calculus, we obtain

$\int\limits_{1}^{\sqrt{3}}\frac{\text{dx}}{1+\text{x}^{2}}=\text{F}(\sqrt{3})-\text{F}(1)$

$=\tan^{-1}\sqrt{3}-\tan^{-1}1$

$=\frac{\pi}{3}-\frac{\pi}{4}$

$=\frac{\pi}{12}$
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MCQ 2041 Mark
Choose the correct answer in Exercises : $\int\frac{\sin^2\text{x}-\cos^2\text{x}}{\sin^2\text{x}\cos^2\text{x}}\text{ dx}$ is equal to
  • $\tan\text{x}+\cot\text{x}+\text{C}$
  • B
    $\tan\text{x}+\text{cosec x}+\text{C}$
  • C
    $-\tan\text{x}+\cot\text{x}+\text{C}$
  • D
    $\tan\text{x}+\sec\text{x}+\text{C}$
Answer
Correct option: A.
$\tan\text{x}+\cot\text{x}+\text{C}$
$\int\frac{\sin^2\text{x}-\cos^2\text{x}}{\sin^2\text{x}\cos^2\text{x}}\text{ dx}$
$=\int\bigg(\frac{\sin^2\text{x}}{\sin^2\text{x}\cos^2\text{x}}-\frac{\cos^2\text{x}}{\sin^2\text{x}\cos^2\text{x}}\bigg)\text{dx}$
$=\int(\sec^2\text{x}-\text{cosec}^2\text{x})\text{ dx}$
$=\tan\text{x}+\cot\text{x}+\text{C}$
Hence, the correct answer is $A$.
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MCQ 2051 Mark
The derivative of $\text{f(x)}=\int\limits^{\text{x}^3}_{\text{x}^2}\frac{1}{\log_{\text{e}}\text{t}}\text{ dt},(\text{x}>0),$ is:
  • A
    $\frac{1}{3\ln\text{x}}$
  • B
    $\frac{1}{3\ln\text{x}}-\frac{1}{2\ln\text{x}}$
  • $\big(\ln\text{x}\big)^{-1}\text{x}(\text{x}-1)$
  • D
    $\frac{3\text{x}^2}{\ln\text{x}}$
Answer
Correct option: C.
$\big(\ln\text{x}\big)^{-1}\text{x}(\text{x}-1)$
$\text{f}'(\text{x})=\frac{1}{\log_\text{e}\text{x}^3}(3\text{x}^2)-\frac{1}{\log_\text{e}\text{x}^2}(2\text{x})$

$=\frac{3\text{x}^2}{3\ln\text{ x}}-\frac{2\text{x}}{2\ln\text{ x}}$

$=\frac{\text{x}^2}{\ln\text{ x}^{-1}}-\frac{\text{x}}{\ln\text{ x}}$

$=\frac{1}{\ln\text{ x}}\text{x}(\text{x}-1)$

$=\big(\ln\text{ x}\big)^{-1}\text{x}(\text{x}-1)$
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MCQ 2061 Mark
$\int\frac{\sin^2\text{x}-\cos^2\text{x}}{\sin^2\text{x}\cos^2\text{x}}\text{dx}$ is equal to:
  • A
    $\tan\text{x}+\cos\text{x}+\text{c}$
  • B
    $\tan\text{x}+\text{cosec}\ \text{x}+\text{c}$
  • $\tan\text{x}+\text{cot}\ \text{x}+\text{c}$
  • D
    $\tan\text{x}+\sec\text{x}+\text{c}$
Answer
Correct option: C.
$\tan\text{x}+\text{cot}\ \text{x}+\text{c}$
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MCQ 2071 Mark
$\int\log_{10}\text{xdx}=$
  • A
    $\log_{\text{e}}10.\text{x}\log_{\text{e}}\big(\frac{\text{x}}{\text{e}}\big)+\text{c}$
  • $\log_{10}\text{e.x}\log_{\text{e}}\big(\frac{\text{x}}{\text{e}}\big)+\text{c}$
  • C
    $\log_{10}\text{e.x}\log_{\text{e}}\big(\frac{\text{x}}{\text{e}}\big)+\text{n}$
  • D
    $\log_{10}\text{e.x}\log_{\text{e}}\big(\frac{\text{x}}{\text{n}}\big)+\text{n}$
Answer
Correct option: B.
$\log_{10}\text{e.x}\log_{\text{e}}\big(\frac{\text{x}}{\text{e}}\big)+\text{c}$
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MCQ 2081 Mark
$\int\limits^\frac{\pi}{2}_{-\frac{\pi}{2}}\sin|\text{x}|\text{dx}$ is equal to:
  • A
    1
  • 2
  • C
    -1
  • D
    -2
Answer
Correct option: B.
2
$\int\limits^\frac{\pi}{2}_{-\frac{\pi}{2}}\sin|\text{x}|\text{dx}$

$=-\int\limits^0_{-\frac{\pi}{2}}\sin\text{x}\text{ dx}+\int\limits^\frac{\pi}{2}_0\sin\text{x}\text{ dx}$

$=-\big[-\cos\text{x}\big]^0_{-\frac{\pi}{2}}+\big[-\cos\text{x}\big]^\frac{\pi}{2}_0$

$=1-0-0+1$

$=2$
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MCQ 2091 Mark
$\lim\limits_{\text{n}\rightarrow\infty}\Big\{\frac{1}{2\text{n}+1}+\frac{1}{2\text{n}+2}+\ .....+\frac{1}{2\text{n}+\text{n}}\Big\}$ is equal to:
  • A
    $\ln\Big(\frac{1}{3}\Big)$
  • B
    $\ln\Big(\frac{2}{3}\Big)$
  • $\ln\Big(\frac{3}{2}\Big)$
  • D
    $\ln\Big(\frac{4}{3}\Big)$
Answer
Correct option: C.
$\ln\Big(\frac{3}{2}\Big)$
$\lim\limits_{\text{n}\rightarrow\infty}\Big\{\frac{1}{2\text{n}+1}+\frac{1}{2\text{n}+2}+\ .....\ +\frac{1}{2\text{n}+\text{n}}\Big\}$

$=\lim\limits_{\text{n}\rightarrow\infty}\sum\limits^\text{n}_{\text{r}=1}\frac{1}{2\text{n}+\text{r}}$

$=\lim\limits_{\text{n}\rightarrow\infty}\frac{1}{\text{n}}\sum\limits^\text{n}_{\text{r}=1}\frac{1}{2+\frac{\text{r}}{\text{n}}}$

let $\frac{\text{r}}{\text{n}}=\text{x}$

$=\int\limits^\infty_0\frac{1}{2+\text{x}}\text{dx}$

$=\Big[\log\big(2+\text{x}\big)\Big]^\infty_0$

$=\log3-\log2$

$=\log\frac{3}{2}$

$=\ln\Big(\frac{3}{2}\Big)$
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MCQ 2101 Mark
What is the value of $\int_{0}^{\frac{ \pi}{2}}\frac{\sqrt{\tan\text{x}}}{\sqrt{\tan}\ \text{x}+\sqrt{\cot}\ \text{x}}\text{dx}?$
  • A
    $\frac{\pi}{2}$
  • $\frac{\pi}{4}$
  • C
    $\frac{\pi}{8}$
  • D
    None of these
Answer
Correct option: B.
$\frac{\pi}{4}$
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M.C.Q (1 Marks) - Page 5 - MATHS STD 12 Science Questions - Vidyadip