Math, asked by nikhilvk, 1 year ago

x³+y³ = 91, x+y=7 then xy=?

Answers

Answered by abhi569
9
(x+y) = 7

cube on both sides,

(x+y)^3 = 7^3 

by formula,

x^3 +y^3 +3xy(x+y) = 343

put the values which are given,

91+21xy = 343

21xy = 343-91

21xy = 252

xy= 252/21

12 = xy



abhi569: your welcome nova
nikhilvk: abhi which formula you used
abhi569: hi
abhi569: (a+b)^3
abhi569: is used here
Answered by kshitijNGU
2
I Hope it will help u
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