Question

if (y-1/y)whole cube = 27,then find the value of y cube - 1/y cube.

Answer 1

Answer:

y^3-(1÷y) ^3=3y^2+27y+3

Step-by-step explanation:

(y-1÷y)^3=27

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

so, (y-1÷y)^3=y^3-(1÷y)^3-3(y)(1÷y)(y-1÷y)

27= y^3-(1÷y)^3-3(y-1÷y)

y^3-(1÷y)^3=27+3y+3÷y

=27y+3y^2+3

=3y^2+27y+3