Question

solve maths class 9​

Answer 1

Step-by-step explanation:

it factories by two methods

first is from identity

second by direct factories

I tell by identity

we have to use 6 identity for

1.question

Answer 2

Answer:

i(4a +5b )(4a +5b )(4a +5b )

ii) (5x - 3y) (5x - 3y) (5x - 3y)

iii) didn't understand very sorry

iv)

Step-by-step explanation:

i) $64a^3 + 125b^3 + 240a^2b + 300ab^2$

$(4a)^3 + (5b)^3 + 3(4a)^2(25b) + 3(4a)(5b)^2\\a^3 + b^3 + 3a^2b +3ab^2 = (a+b)^3\\\\=(4a + 5b)^3\\=(4a +5b)(4a+5b)(4a+5b)$

where a= 4a and b = 5b

ii

 $125x^3 -27x^3 -225x^2y +135xy^2\\(5x)^3 - (3y)^3 - 3(5x)^2(3y) + 3(5x)(3y)^2\\a^3 - b^3 -3a^2b +3ab^2 = (a-b)^3\\=(5x-3y)^3\\=(5x-3y)(5x-3y)(5x-3y)$

where a= 5x & b = 3y

iii) didn't understand sorry

iv)

$8x^3 +27y^3 +36x^2y +54xy^2\\(2x)^3 +(3y)^3 + 3(2x)^2(3y) + 3(2x)(3y)^2\\a^3 +b^3 +3a^2b + 3ab^2= (a+b)^3\\=(2x +3y)^3\\=(2x+3y)(2x+3y)(2x+3y)$