问题
选择题
下列计算中,错误的是( ) |
A.(x+1)(x+4) =x2+5x+4 B.(m一2)(m+3) =m2+m一6 C.(y+4)(y一5) =y2+9y一20 D.(x一3)(x一6) =x2一9x+18 |
答案
答案:C
下列计算中,错误的是( ) |
A.(x+1)(x+4) =x2+5x+4 B.(m一2)(m+3) =m2+m一6 C.(y+4)(y一5) =y2+9y一20 D.(x一3)(x一6) =x2一9x+18 |
答案:C