Question 3: Multiply: \((x^2+2xy−3)(−xy)\)
We have:
\( {\mkern 1mu} \left( {{x^2} + 2xy – 3} \right)\left( { – xy} \right) = {x^2}.\left( { – xy} \right ) + 2xy.\left( { – xy} \right) – 3.\left( { – xy} \right) = – {x^3}y – 2{x^2}{y^2} + 3xy\ )
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