Differential Calculus

| x| >1;let y =1+x+x^2+…………to infinity then dy/dx equal to

nitish kumar

16 Years agoGrade

2 Answers

student iit

16 Years ago

This is infinite GP where common ration x>1.

S(n)= 1(x^n-1)/(x-1)= x^n-1/x-1

Now use d(u/v)/dx formula to find the drivative.

Badiuddin askIITians.ismu Expert

16 Years ago

hi nitish kumar

| x| >1;

y =1+x+x^2+…………to infinity

dy/dx =1+2x+3x²+4x³ .....................infinity

clearl for x>1 dy/dx tends to +infinity

and for x<-1 dy/dx tends to either + infinity or - infinity

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