Question

The co-efficient of x 49 is the expression of (x + 1) (x + 2) (x + 3) ...... (x+50) is
A. 1285
B. 1295
C. 1275
D. 1290
​

Answer 1

The coefficient of X will be the sum of numbers from 1 to 50*

Sum of numbers from 1 to n = n(n+1)/2

= 50×51/2

= 1275

Ans: 1275

You will notice that for the power X^49, out of the 50 X's 49 will be there and one number will be there. This shall be done 50 times for all 50 numbers.

Hope this helps you...