If a-b= 6 and ab = 20 find a^3 -b^3
Answers
Answered by
56
a^3-b^3
=(a-b)(a^2+b^2+a*b)
=(a-b)((a-b)^2+2*ab +a*b)
=6(36 +40 +20)
=6*96
=576
=(a-b)(a^2+b^2+a*b)
=(a-b)((a-b)^2+2*ab +a*b)
=6(36 +40 +20)
=6*96
=576
Answered by
57
Hey there!
Praneeth from Brainly.in here to help!
Given
➻ ab=20,
➻ (a-b)=6
➟ (a-b)³=a³-b³-3ab(a-b)
➟ (a-b)³=a³-b³-3a²b+3ab²
➟a ³-b³=(a-b)³+3ab(a-b)
➺ 6³+3*20(6)
➺ 216+360
➺ 576
∴a³-b³=576
hope helped!
Praneeth from Brainly.in here to help!
Given
➻ ab=20,
➻ (a-b)=6
➟ (a-b)³=a³-b³-3ab(a-b)
➟ (a-b)³=a³-b³-3a²b+3ab²
➟a ³-b³=(a-b)³+3ab(a-b)
➺ 6³+3*20(6)
➺ 216+360
➺ 576
∴a³-b³=576
hope helped!
Similar questions