The given equation is
[tex]f(x)=2x^3-3x^2+7[/tex]We need to find f(-1)
That means substitute x by -1 in the given function
[tex]f(-1)=2(-1)^3-3(-1)^2+7[/tex]since (-1)^3 = -1 ------- (-1)(-1)(-1) = -1
Since (-1)^2 = 1 -------- (-1)(-1) = 1, then
[tex]\begin{gathered} f(-1)=2(-1)-3(1)+7 \\ f(-1)=-2-3+7 \\ f(-1)=-5+7 \\ f(-1)=2 \end{gathered}[/tex]Then f(-1) = 2