Question 417393
We differentiate this type of expression in the following way:
Let {{{u = 1+5x}}}, then we have {{{y = u^3}}}
We want to find {{{dy/dx = (dy/du)*(du/dx)}}}
{{{dy/du = 3u^2}}} and {{{du/dx = 5}}}
Thus {{{dy/dx = 3(1+5x)^2*5 = 15(1+5x)^2}}}