Question

3tan^3 x=tanx

Answer 1

for ease of typing, let y = tan(x)
then
3tan^3 x=tanx can be written as
\[ 3 y^3 = y \]
or, subtract y from both sides to get
\[ 3y^3 - y=0\]
factor out a y from both terms
\[ y(3y^2-1) = 0\]
can you solve for y?