a) A = (√3+3) * (3√3+2) = 3*3+2√3+9√3+6= 9 + 11√3+6 = 15+11√3 cm²
b) (5√5+1) * (√5-1) = 5*5-5√5+√5-1 = 25 - 4√5-1 = 24-4√5 cm2
c) (6√3-3√2) * (6√3+3√2) = (6√3)² - (3√2)² = 36*3-9*2=108-18=90 cm²
d) (2√2-√3) * (3√2-2√3) = 6*2-4√6-3√6+2*3= 12-7√6+6 = 18-7√6 cm2