(a-5)(a-1)-(a+2)(a-3) при a=-2 3/5

Question

(a-5)(a-1)-(a+2)(a-3) при a=-2 3/5

Answer 1

(а-5)(а-1)-(а+2)(а-3)=а²-а-5а+5-(а²-3а+2а-6)=а²-а-5а+5-а²+3а-2а+6=-5а+11=11-5а

a=-2

11-5а=11-5(-2)=11+10=21