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(y+2)(3y-5)=3y²-5y+6y-10=3y²+y-10
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(7x-3y)(2x+5y)=14x²+35xy-6xy-15y²=14x²+29xy-15y²
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(x-1)(x²-x-2)=x³-x²-2x-x²+x+2=x³-2x²-x+2
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