if 2x + 3y =2 and xy=6 , find the value of 8x^3 + 27 y^3.
Answers
Answered by
0
Step-by-step explanation:
Answer. Given: 2x+3y=13 and xy=6 ——(2)
to find the value of 8x³+27y³
=>2x+3y=13
.(1)
lets us cube both the sides
=>(2x+3y)³ = 133
=> (2x)3 + (3y)3 + 3 (2x) (3y) (2x + 3y) =2197 {applying the
formula (a+b)³ =
a³ + b³ + 3ab(a+b)}
=> 8x³ + 27 y³ + 18 xy(13)= 2197.
=>
8x3+27 y3 +18 (6)(13)= 2197
8x³+27 y³ = 2197 - 1404
=> 8x³+27 y³ = 793 Answer
Similar questions