Department of Pre-University Education, KarnatakaPUC Karnataka Science Class 11

# Find the 7th Term from the End in the Expansion of ( 2 X 2 − 3 2 X ) 8 . - Mathematics

Find the 7th term from the end in the expansion of $\left( 2 x^2 - \frac{3}{2x} \right)^8$ .

#### Solution

Let Tr+1 be the 7th term from the end in the given expression.
Then, we have:
Tr+1 = (9 − 7 + 1) =  3rd term from the beginning
Now,

$T_3 = T_{2 + 1}$
$= ^{8}{}{C}_2 (2 x^2 )^{8 - 2} \left( - \frac{3}{2x} \right)^2$
$= \frac{8 \times 7}{2 \times 1}\left( 64 x^{12} \right)\frac{9}{4 x^2}$
$= 4032 x^{10}$

Concept: Rth Term from End
Is there an error in this question or solution?

#### APPEARS IN

RD Sharma Class 11 Mathematics Textbook
Chapter 18 Binomial Theorem
Exercise 18.2 | Q 8 | Page 37