Question

If `y=3^(1/3)+3`,then `y^3-9y^2+27 y=`____
A. 27
B. `-27`
C. `-30`
D. 30

Answer 1

Correct Answer - D
Given , `y=3^(1//3)+3`
`implies y-3=3^(1//3)`
Taking the cube on both sides
`implies (y-3)^(3)=(3^(1//3))^(3)`
`implies y^(2)-9y^(2)+27y-27=3`
`implies y^(3)-9y^(2)+27y=30`