If x^2+y^2=58 and x+y=10 then find value of x^3+y^3
Answers
Answered by
23
Hey! Here's your answer!
x + y = 10
x = y - 10
(y - 10)^2 + y^2 = 58
y^2 - 20y + 100 + y^2 = 58
2y^2 - 20y + 42 = 0
2y^2 - 6y - 14y + 42 = 0
2y(y - 3) - 14(y - 3) = 0
y = 7 or y = 14
x = 3 or x = -4
Say, x = 3 and y = 7,
x^3 + y^3 = 3*3*3 + 7*7*7
= 27 + 343
x^3 + y^3 = 370
Hope this helps! :)
AccioNerd:
If you want, you can also take y = 14 and x = 4
Answered by
14
HELLO USER :-) HERES UR ANSWER
x^3+y^3= (x+y)(x^2-xy+y^2)
= (10)(58-xy)
______________________
NOW WE NEED TO FIND xy
WE KNOW:-
(x+y)^2= x^2+y^2+2xy
100=58+2xy
42=2xy
21=xy
_________________________
NOW COMING BACK TO x^3+y^3
x^3+y^3=(10)(58-xy)
=(10)(58-21)
=(10)(37)
=10×37
=370
SO THE ANSWER IS 370
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PLZ MARK AS BRAINLIEST.......
x^3+y^3= (x+y)(x^2-xy+y^2)
= (10)(58-xy)
______________________
NOW WE NEED TO FIND xy
WE KNOW:-
(x+y)^2= x^2+y^2+2xy
100=58+2xy
42=2xy
21=xy
_________________________
NOW COMING BACK TO x^3+y^3
x^3+y^3=(10)(58-xy)
=(10)(58-21)
=(10)(37)
=10×37
=370
SO THE ANSWER IS 370
___________________
IF YOU HAVE ANY DOUBT STILL U CAN ASK ME......
HAVE A NICE DAY.....
HOPE IT HELPS U......
PLZ MARK AS BRAINLIEST.......
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