Question

1)(a+1)(a+1)=?
2)(2+y)(y+3)=?
3)(1+x)(1-x)=?
4)(2a+b)(a+2b)=?

Answer 1

$(a+1)(a+1)=a^2+a+a+1^2=a^2+2a+1 (2+y)(y+3)=2y+2*3+y^2+3y=5y+6+y^2 (1+x)(1-x)=1^2-x^2 (2a+b)(a+2b)=2a^2+2b*2b+ab+2b*b=2a^2+4b^2+ab+2b^2=2a^2+6b^2+ab$