Question

Answer this fast please​

Answer 1

Answer:

Given that:

(2a²+3b²)(5a²-6b²)

Using distributive property

=>(2a²)(5a²-6b²)+(3b²)(5a²-6b²)

=>10a¹-12a²b²+15a²b²-18b4

=>10a+3a²b²-18b4

(2a²+3b²)(5a²-6b²)=10a^+3a²b²-18bª

Used concept:

Distributive property:

Let a, b, c be the three numbers, 9 9 if ax(b+c)= (axb)+(axc)

is called distributive property unde multiplication over addition.Given that:

(2a²+3b²)(5a²-6b²)

Using distributive property

=>(2a²)(5a²-6b²)+(3b²)(5a²-6b²)

=>10a¹-12a²b²+15a²b²-18b4

=>10a+3a²b²-18b4

(2a²+3b²)(5a²-6b²)=10a^+3a²b²-18bª

Used concept:

Distributive property:

Let a, b, c be the three numbers, 9 9 if ax(b+c)= (axb)+(axc)

is called distributive property unde multiplication over addition.

Answer 2

Step-by-step explanation:

This is because , we get a^3 +b^3 by expanding (a+b)^3. In which all terms are positive only. But then few terms of this expansion are transposed to the other side of the equation, converting those positive to negative .

(a+b)^3 = a^3 + b^3 + 3a^2 b + 3ab^2

=> a^3 + b^3 = (a+b)^3 - 3a^2b -3ab^2

=> a^3 + b^3 = (a+b)^3 -3ab(a+b)

=> a^3 + b^3 = (a+b) {( a+b)^2 - 3ab}

=> a^3 + b^3 = (a+b)(a^2+ b^2 +2ab-3ab)

=> a^3 +b^3 = (a+b) ( a^2 -ab + b^2)

This is how term 'ab' becomes negative