问题
填空题
已知(x-p)(x+3)=x2+2x+q,则p+q=______.
答案
∵(x-p)(x+3)=x2+(3-p)x-3p=x2+2x+q,
∴3-p=2,-3p=q,
解得:p=1,q=-3,
则p+q=1-3=-2.
故答案为:-2
已知(x-p)(x+3)=x2+2x+q,则p+q=______.
∵(x-p)(x+3)=x2+(3-p)x-3p=x2+2x+q,
∴3-p=2,-3p=q,
解得:p=1,q=-3,
则p+q=1-3=-2.
故答案为:-2