Question

(a+1) (2a-1) -(3a-1) (a+3).​

Answer 1

Answer:

-a^2- 11a+4 is the answer

Answer 2

Answer:

If a, b, c are in AP then 2b=a+c

So,

2(a2+a+1)=3a²− 3a+3+2a+1

2a²+2a+2=3a²−a+4

⇒3a²−2a²−a−2+4−2=0

⇒a²−3a+2=0

⇒a²−2a−a+2=0

⇒a(a−2)−1(a−2)=0

So (a−1)(a−2)=0

So a=1 or a=2.