Factors of (a + b)3 - (a - b)3 is :
(A) 2ab(3a2 + b2) (B) ab(3a2 + b2) (C) 2b(3a2 + b2) (D) 3a2 + b2
Answers
Answer:
a3 + b3
Step-by-step explanation:
First of all let us know what is (a+b)^3 (“^” This is a power symbol)
Since the expression is derived from (a+b)^3
So let us expand it
So let us expand it(a+b)^3
So let us expand it(a+b)^3= (a+b) (a+b) (a+b)
So let us expand it(a+b)^3= (a+b) (a+b) (a+b)={(a+b) (a+b)} (a+b)
So let us expand it(a+b)^3= (a+b) (a+b) (a+b)={(a+b) (a+b)} (a+b)={a(a+b) + b(a+b)} (a+b)
So let us expand it(a+b)^3= (a+b) (a+b) (a+b)={(a+b) (a+b)} (a+b)={a(a+b) + b(a+b)} (a+b)=(a^2 + ab + ab + b^2) (a+b)
So let us expand it(a+b)^3= (a+b) (a+b) (a+b)={(a+b) (a+b)} (a+b)={a(a+b) + b(a+b)} (a+b)=(a^2 + ab + ab + b^2) (a+b)=(a^2 + b^2 + 2ab) (a+b)
So let us expand it(a+b)^3= (a+b) (a+b) (a+b)={(a+b) (a+b)} (a+b)={a(a+b) + b(a+b)} (a+b)=(a^2 + ab + ab + b^2) (a+b)=(a^2 + b^2 + 2ab) (a+b)=a^2(a+b) + b^2(a+b) + 2ab(a+b)
So let us expand it(a+b)^3= (a+b) (a+b) (a+b)={(a+b) (a+b)} (a+b)={a(a+b) + b(a+b)} (a+b)=(a^2 + ab + ab + b^2) (a+b)=(a^2 + b^2 + 2ab) (a+b)=a^2(a+b) + b^2(a+b) + 2ab(a+b)=a^3 + a^2b + ab^2 + b^3 + 2a^2b + 2ab^2
So let us expand it(a+b)^3= (a+b) (a+b) (a+b)={(a+b) (a+b)} (a+b)={a(a+b) + b(a+b)} (a+b)=(a^2 + ab + ab + b^2) (a+b)=(a^2 + b^2 + 2ab) (a+b)=a^2(a+b) + b^2(a+b) + 2ab(a+b)=a^3 + a^2b + ab^2 + b^3 + 2a^2b + 2ab^2=a^3 + b^3 + 3a^2b + 3ab^2
So let us expand it(a+b)^3= (a+b) (a+b) (a+b)={(a+b) (a+b)} (a+b)={a(a+b) + b(a+b)} (a+b)=(a^2 + ab + ab + b^2) (a+b)=(a^2 + b^2 + 2ab) (a+b)=a^2(a+b) + b^2(a+b) + 2ab(a+b)=a^3 + a^2b + ab^2 + b^3 + 2a^2b + 2ab^2=a^3 + b^3 + 3a^2b + 3ab^2=a^3 + b^3 + 3ab(a+b)
Now when we have expanded (a+b)^3 = a^3 + b^3 + 3ab(a+b)
We can equate it
(a+b)^3 = a^3 + b^3 + 3ab(a+b)
(a+b)^3 = a^3 + b^3 + 3ab(a+b)(a+b)^3 - 3ab(a+b) = a^3 + b^3
(a+b)^3 = a^3 + b^3 + 3ab(a+b)(a+b)^3 - 3ab(a+b) = a^3 + b^3a^3 + b^3 = (a+b)^3 - 3ab(a+b)
Let us graphically represent this formula:
Let us assume
Let us assumea = 1cm and b = 2cm
(a+b)^3
which is equal to a^3 + b^3 + 3a^2b + 3ab^2
So when we make a cube by adding a+ b we get 3 times of a^2b and 3 times of ab^2
Hope this could help you friend ;)
Answer:
a3+b3
Step-by-step explanation: