Hi GYES can any one tell me this solution x^3+y^3+z^3-3xyz if x+y+z=12 and x^2+y^2+z^2=70 please note spam it is 90 points answer
Answers
Answered by
8
Answer:
396
Step-by-step explanation:
We have:
x + y + z = 12 and x² + y² + z² = 70.
Then:
(x + y + z)² = x² + y² + z² + 2xy + 2yz + 2zx
⇒ (12)² = 70 + 2(xy + yz + zx)
⇒ 144 - 70 = 2(xy + yz + zx)
⇒ 74 = 2(xy + yz + zx)
⇒ xy + yz + zx = 37
Now,
x³ + y³ + z³ - 3xyz
= (x + y + z)(x² + y² + z² - xy - yz - zx)
= (x + y + z)(x² + y² + z² - (xy + yz + zx))
= (12)(70 - 37)
= 12 * 33
= 396
Hope it helps!
siddhartharao77:
:-)
Answered by
1
x³ + y³ + z³ - 3xyz
= (x + y + z)(x² + y² + z² - xy - yz - zx)
= (x + y + z)(x² + y² + z² - (xy + yz + zx))
= (12)(70 - 37)
= 12 * 33
= 396
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