Question

A=(x-3)(x+3)-(x+2)(x-1) tại x=1/3

Answer 1

\(A=x^2-9-x^2-x+2=-x-7=-\dfrac{1}{3}-7=-\dfrac{22}{3}\)

Answer 2

\(A=\left(x-3\right)\left(x+3\right)-\left(x+2\right)\left(x-1\right)=x^2-9-\left(x^2+x-2\right)=x^2-9-x^2-x+2=-x-7=-\dfrac{1}{3}-7=-\dfrac{22}{3}\)