急解数学题 答了给分 要过程

1. (2a+1)^2-2(2a+1)+3
=(2a+1-1)^2+2
=4a^2+2=10
2. (a-√3)(a+√3)-a(a-6)
=a^2-3-a^2+6a
=6a-3=6√5+3-3=6√5
3. (3a^2-ab+7)-(5ab-4a^2+7)
=3a^2-ab+7-5ab+4a^2-7
=7a^2-6ab=7*4-6*2/3=28-4=24