7.Binomial Theorem
hard

$(\mathrm{x}+\sqrt{\mathrm{x}^{2}-1})^{6}+(\mathrm{x}-\sqrt{\mathrm{x}^{2}-1})^{6}$ ના વિસ્તરણમાં  $x^{4}$ અને $x^{2}$ ના સહગુણકો $\alpha$ અને $\beta$ હોય તો  . . . .  

A

$\alpha+\beta=60$

B

$\alpha+\beta=30$

C

$\alpha-\beta=-132$

D

$\alpha-\beta=60$

(JEE MAIN-2020)

Solution

$2\left[^{6} \mathrm{C}_{0} \mathrm{x}^{6}+^{6} \mathrm{C}_{2} \mathrm{x}^{4}\left(\mathrm{x}^{2}-1\right)+6 \mathrm{C}_{4} \mathrm{x}^{2}\left(\mathrm{x}^{2}-1\right)^{2}+^{6} \mathrm{C}_{6}\left(\mathrm{x}^{2}-1\right)^{3}\right]$

$\alpha=-96 \;and\; \beta=36$

$\therefore \alpha-\beta=-132$

Standard 11
Mathematics

Similar Questions

Start a Free Trial Now

Confusing about what to choose? Our team will schedule a demo shortly.