First slide

Binomial theorem for positive integral Index

Question

Sum of the coefficients of ${(1 + x - 3 x^{2})}^{171} =$

Easy

A

1
B

2
C

3
D

$- 1$

Solution

Given expansion ${(1 + x - 3 x^{2})}^{171}$ is
Sum of the coefficients of ${(1 + x - 3 x^{2})}^{171}$

Let consider $f (x) = {(1 + x - 3 x^{2})}^{171}$ substitute $x = 1$ then we get

$\Rightarrow f (1) = {(1 + 1 - 3)}^{171}$

$\Rightarrow f (1) = {(- 1)}^{171} = - 1$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App