Question

if x2+y2 =49and x-y=3 then find the value of x3-y3

Answer 1

ANSWER:
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Given that,
x2+y2=49
x-y=3

We Know That,
(x-y)^2=x2-2xy+y2
=>3^2 =49-2xy
=>9=49-2xy
=>49-2xy=9
=>-2xy=9-49
=>-2xy= - 40
=>xy = -40 ÷ (-2)
=>xy = 20

By Putting the Value of x3-y3,
We get
x3-y3
=(x-y)(x2+y2+xy)
=3(49+xy)
=3×49+20
=3×69
= 207 (Ans)
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Hope this is correct and Useful for you.
Thanks.

Answer 2

See the pic below , if any doubts ask me . Hope you like the answer