This is LaTeX code:
[latex]
f^{*}(e_{1})=(1-t-t^{2})(-1)+(1-t-t^{2})(1)+(1-t-t^{2})(1)(0)=1-1+1=1=\alpha_1 \\ f^{*}(e_{2})=0+2+1=3=\alpha_2 \\ f^{*}(e_{3})=-2+0+0=-2=\alpha_3 \\ f^{*}(e_{4})=-2+2+0=0=\alpha_4
[/latex]