Ask Me Help Desk - How can I calculate this? 4x^3=3.0x10^-16

I assume that what you mean is this:

$ 4 x^3 = 3.0 \times 10^{-16} $

First divide through by 4:

$ x^3 = 7.5 \times 10{-17} $

Then take the cube root of both sides:

$ \sqrt[3] {x^3} = \sqrt[3] {7.5 \times 10 ^{-17}} \\ x = (7.5 \times 10 ^{-17})^{1/3} = (7.5 \times 10 \times 10 ^ {-18} ) ^{1/3} \\ = 75^{1/3} \times 10 ^ {-6}\\ = 4.217 \times 10^{-6} $

Notice how by changing the exponent of 10 from $10^ {-17}$ to $10 \times 10^ {-18}$ it makes it easy to divide by 3 to get $10^{-6}$