A,
[tex] \sqrt{12 = \sqrt{4} } \times \sqrt{3 } = 2 \sqrt{3 } = [/tex]
B,
[tex] \sqrt{3} \times \sqrt{6} = \sqrt{18} = \sqrt{9} \times \sqrt{2 } = 3 \sqrt{2} [/tex]
C,
[tex] \sqrt{8} = 2 \sqrt{2} [/tex]
[tex]2 \sqrt{2} + \sqrt{2} = 3 \sqrt{2} [/tex]
A(x)=x^2+x-2
B(x)=-x^2+5x