If x+1/x = 20, find x²+1/x² and x³+1/x³ using algebraic identities.
kvnmurty:
(x+1/x)^3 = x^3 + 1/x^3 + 3 (x+1/x) x*1/x => x^3 + 1/x^3 = 8000 - 3*20 = 7940
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(x + 1/x)^2 = 20^2
x^2+(1/x)^2+2 x x x 1/x=400
x^2+1/x^2+2x/x=400
thereforex^2+1/x^2=400-2=398
sry tried the second one but im not able to do
x^2+(1/x)^2+2 x x x 1/x=400
x^2+1/x^2+2x/x=400
thereforex^2+1/x^2=400-2=398
sry tried the second one but im not able to do
even i don't know for the second one
did u knew d 1st 1
yes.
kkkk
hello
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