Question

If a3+ b3 = 19 and a + b = 1, then what is the value of ab?

A) 5 B) -6 C) 7 D) -9

Answer 1

Answer:

correct answer ===> option B) -6

explanation ↓

since , a³ + b³ = ( a + b)³ -3ab( a + b)

=> 19 = 1³ -3ab * 1

=> 19 = 1 - 3ab

=> 19 -1 = -3ab

=> 18 = -3ab

=> ab = - 18/3

=> ab = -6

wo,

the value of ab is => -6.

$.$

Answer 2

Hello mate

Option B

-6

Hope it helps