Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • NCERT
  • If The middle term of (1/x + x sin x)^10 is equal to 7 7/8then the value of x is A. 2n pi + pi/6 B. n pi + pi/6

If the middle term of \left ( \frac{1}{x} + x \sin x \right )^{10} is equal to 7\tfrac{7}{8} then the value of x is 

(a) 2n\pi + \frac{\pi}{6}  (b) n\pi + \frac{\pi}{6}  (c) n\pi +\left ( -1 \right )^{n} \frac{\pi}{6} (d) n\pi +\left ( -1 \right )^{n} \frac{\pi}{3}

Answers (1)

The answer is the option (c) nπ + (-1)nπ/6

Now, n = 10 (even)

Thus, there is only one middle term i.e., the 6th term

Thus, T6 = T5+1

                 = 10C5(1/x)10-5 (x sin x)5

63/8 = 10C5 sin5x   …… (given)

                63/8 = 252 x sin5x

Thus, sin5x = 1/32

Sin x = ½

Sin x = π/6

Thus, x = nπ + (-1)nπ/6

Posted by

infoexpert22

View full answer

Similar Questions

Latest Question