a) (√3+1)(2√3-2)=2(√3×√3)-2√3+2√3-2=2×6-2√3+2√3=12
b) (√2+√3)(√5+1)=√10+√2+√15+√3
c) (√2+1)(5-2√2)=5√2-2(√2×√2)+5-2√2=5√2-2×2+5-2√2=5√2+1-2√2=3√2+1
d) (2+√2)(2√2+3)=4√2+6+2(√2×√2)+3√2=4√2+6+4+3√2=7√2+10
