Question

if 2a + b = 6, then show that 8a³ +b³ + 36ab = 216​

Answer 1

Answer:

JUST CUBE ON BOTH SIDES

Step-by-step explanation:

(2A+B)³=6³

(A+B)³=A³+B³+3A²B+3AB²(FORMULA)

(2A)³+B³+3(2A)²(B)+3(2A)(B²)=216

8A³+B³+6AB(2A+B)=216. (BY TAKING 6AB COMMON ON BOTH SIDES)

GIVEN THAT 2A+B=6

8A³+B³+6AB(6)=216

8A³+B³+36AB=216

HENCE PROVED

MARK ME AS BRAINLIEST!!

Answer 2

Answer:

I have already given this answer in your previous question.Again I give you.

∆Given equation: 2a+b=6

L.H.S=8a³+b³+36ab

=(2a)³+b³+36ab

=(2a+b)³-3×2a×b(2a+b)+36ab[Read at last for formula)

=(6)³-6ab×6+36ab

=216-36ab+36ab

=216[36ab plus and minus cancel out]=R.H.S(Proved)

At last I say you the formula,

♦a³+b³=(a+b)(a²-ab+b²) and it have also a formula

♦=(a+b)³-3ab(a+b)