Question

If a²+b² =90and ab = 27,where a and b are greater than zero, then find a³+b³​

Answer 1

Answer:

a³ + b³ = 636

Step-by-step explanation:

Given : a²+b² =90  and ab = 27

( a + b )² = a² + b² + 2ab

( a + b )² = 90+ 2(27)

( a + b )² = 90 + 54

( a + b )² =144

a + b = 12                          --- (1)

a³ + b³ = (a + b)( a² + b² - ab)

        Putting all the value from given,

           = 12( 90 - 27)

           = 12 ( 53)

           = 636

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