Badiuddin askIITians.ismu Expert
Last Activity: 14 Years ago
Dear manan
(a+bx)^(-3)=1/8+9/8x+......
u can solve it by using binomial theorem
here just put x= 0
(a)^(-3)=1/8
a =2
now differentiate
-3(a+bx)-4(b) = 9/8 + ........
now put x=0
-3b/a4 =9/8
-3b/16 =9/8
b =-6
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Badiuddin