NCERT Solutions
Class 12 - Mathematics Part-2 - Chapter 7: INTEGRALS
Exercise 7.7

Question. 1

Integrate \(\sqrt{4-x^2}\).

Answer:

\(\dfrac{1}{2}x\sqrt{4-x^2}+2\sin^{-1}\!\left(\dfrac{x}{2}\right)+C\)

Question. 2

Integrate \(\sqrt{1-4x^2}\).

Answer:

\(\dfrac{1}{4}\sin^{-1}(2x)+\dfrac{1}{2}x\sqrt{1-4x^2}+C\)

Question. 3

Integrate \(\sqrt{x^2+4x+6}\).

Answer:

\(\dfrac{x+2}{2}\sqrt{x^2+4x+6}+\log\left|x+2+\sqrt{x^2+4x+6}\right|+C\)

Question. 4

Integrate \(\sqrt{x^2+4x+1}\).

Answer:

\(\dfrac{x+2}{2}\sqrt{x^2+4x+1}-\dfrac{3}{2}\log\left|x+2+\sqrt{x^2+4x+1}\right|+C\)

Question. 5

Integrate \(\sqrt{1-4x-x^2}\).

Answer:

\(\dfrac{5}{2}\sin^{-1}\!\left(\dfrac{x+2}{\sqrt{5}}\right)+\dfrac{x+2}{2}\sqrt{1-4x-x^2}+C\)

Question. 6

Integrate \(\sqrt{x^2+4x-5}\).

Answer:

\(\dfrac{x+2}{2}\sqrt{x^2+4x-5}-\dfrac{9}{2}\log\left|x+2+\sqrt{x^2+4x-5}\right|+C\)

Question. 7

Integrate \(\sqrt{1+3x-x^2}\).

Answer:

\(\dfrac{2x-3}{4}\sqrt{1+3x-x^2}+\dfrac{13}{8}\sin^{-1}\!\left(\dfrac{2x-3}{\sqrt{13}}\right)+C\)

Question. 8

Integrate \(\sqrt{x^2+3x}\).

Answer:

\(\dfrac{2x+3}{4}\sqrt{x^2+3x}-\dfrac{9}{8}\log\left|x+\dfrac{3}{2}+\sqrt{x^2+3x}\right|+C\)

Question. 9

Integrate \(\sqrt{1+\dfrac{x^2}{9}}\).

Answer:

\(\dfrac{x}{6}\sqrt{x^2+9}+\dfrac{3}{2}\log\left|x+\sqrt{x^2+9}\right|+C\)

Question.  10

\(\int \sqrt{1+x^2}\,dx\) is equal to

(A)

\(\dfrac{x}{2}\sqrt{1+x^2}+\dfrac{1}{2}\log\left|x+\sqrt{1+x^2}\right|+C\)

(B)

\(\dfrac{2}{3}(1+x^2)^{3/2}+C\)

(C)

\(\dfrac{2}{3}x(1+x^2)^{3/2}+C\)

(D)

\(\dfrac{x^2}{2}\sqrt{1+x^2}+\dfrac{1}{2}x^2\log\left|x+\sqrt{1+x^2}\right|+C\)

Question.  11

\(\int \sqrt{x^2-8x+7}\,dx\) is equal to

(A)

\(\dfrac{1}{2}(x-4)\sqrt{x^2-8x+7}+9\log\left|x-4+\sqrt{x^2-8x+7}\right|+C\)

(B)

\(\dfrac{1}{2}(x+4)\sqrt{x^2-8x+7}+9\log\left|x+4+\sqrt{x^2-8x+7}\right|+C\)

(C)

\(\dfrac{1}{2}(x-4)\sqrt{x^2-8x+7}-3\sqrt{2}\,\log\left|x-4+\sqrt{x^2-8x+7}\right|+C\)

(D)

\(\dfrac{1}{2}(x-4)\sqrt{x^2-8x+7}-\dfrac{9}{2}\log\left|x-4+\sqrt{x^2-8x+7}\right|+C\)

NCERT Solutions Class 12 – Mathematics Part-2 – Chapter 7: INTEGRALS – Exercise 7.7 | Detailed Answers