Question

ajutor... calculat.... 
 a) √3(√27+4√3)
b)(√3+2)²-√12
c)(√45-√5)²-20

Answer 1

a)√3(√27+4√3)=√3(3√3+4√3)=√3×7√3=7×3=21
b)(√3+2)²-√12=(√3²+2×√3×2+2²)-2√3=3+4√3+4-2√3=7+2√3
c)(√45-√5)²-20=(√45²-2×√45×√5+√5²)-20=(45-15+5)-20=35-20=15