If 2x + 3y = 12 . x y= 12 find 8 x^3+ 27 y^3
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8x³+27y³ = (2x)³+(3y)³
2x+3y = 12
squaring on both sides
(2x+3y)²=(12)²
4x²+9y²+12(6) = 144 (xy= 6)
4x²+9y² = 144-72= 72
so , (2x)³+(3y)³ = (2x+3y)(4x²+9y²-xy). (i)
using formula => a³+b³ = (a+b)(a²+b²-ab)
substitute values in (i)
12(72-6) = 12(66) = 792
hope this helps
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2x+3y = 12
squaring on both sides
(2x+3y)²=(12)²
4x²+9y²+12(6) = 144 (xy= 6)
4x²+9y² = 144-72= 72
so , (2x)³+(3y)³ = (2x+3y)(4x²+9y²-xy). (i)
using formula => a³+b³ = (a+b)(a²+b²-ab)
substitute values in (i)
12(72-6) = 12(66) = 792
hope this helps
Read more on Brainly.in - https://brainly.in/question/1377199#readmore
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