please answer this question step by step don't give me just answer explanation needed
Those who will give right answer i will mark as brainliest
Answers
Answer:
Step-by-step explanation:
(2a+b)3-(2a-b)3-6b (2a+b)(2a-b)
= (2a)3+(b)3+3 (2a)2 (b)+3 (2a)(b)2-(2a)3-
(b)3-3(2a)2 (b)-12ab-6b2-12ab+6b2
=8a3+b3+12a2b+6ab2-8a3-b3-12a2b-6ab2-12ab-12ab
All are cutted and only -12ab-12ab are left
So,the answer is -24ab.
Answer:
The answer to u r question is 8b^3
Step-by-step explanation :
before solving this we need to know some of the basics formulae :
(a+b)^3 = a^3 + 3a^2*b + 3ab^2 + b^3
(a-b)^3 = a^3 - 3a^2*b + 3ab^2 - b^3
(a-b)(a+b)=a^2 - b^2
now,
in this problem we will break it in parts first to make it easy ,
(2a+b)^3 ----------(a) [let this be part a
(2a-b)^3 ----------(b) [let this be part b
6b(2a+b)(2a-b)------------(c) [let this be part c
so we will start with a,
(2a+b)^3 [here 2a is 'a' and b is 'b' , so we will apply (a+b)^3]
=(2a)^3 + 3*(2a)^2*b + 3*2a*b^2 + b^3
=8a^3 + 12a^2*b + 6ab^2 + b^3 [lets just leave it like this ]
now we will solve b,
=(2a-b)^3 [here 2a is 'a' and b is 'b' , so we will apply (a-b)^3]
=(2a)^3 - 3*(2a)^2*b + 3*2a*b^2 - b^3
=8a^3 - 12a^2*b + 6ab^2 - b^3 [lets just leave it like this ]
now we will solve c,
6b(2a+b)(2a-b) [here we will apply (a-b)(a+b)=a^2-b^2 as 2a as 'a' & b as 'b']
=6b((2a)^2 - b^2)
=6b(4a^2 - b^2)
=24a^2 *b -6b^3
now we will join a, b , c
that is a-b-c
=8a^3 + 12a^2*b + 6ab^2 + b^3 - [8a^3 - 12a^2*b + 6ab^2 - b^3 ]-[24a^2 *b -6b^3]
=8a^3 + 12a^2*b + 6ab^2 + b^3 - 8a^3 + 12a^2*b - 6ab^2 + b^3 - 24a^2 *b + 6b^3
=we will group the like terms ,
12a^2*b + 12a^2*b + b^3 + b^3- 24a^2 *b + 6b^3
=24a^2*b+2 b^3- 24a^2 *b + 6b^3
=2b^3+6b^3