Question

помогите решить плиз
1)3√300-7√75+√27-5√108+√6
2)-5√5(√125-1/√5+2√20
3)(-2/√3)²+(3√3/√5)²-√216/√6+4/15

Answer 1

$1) .......=3 sqrt{3*100} -7 sqrt{3*25} + sqrt{3*9} -5 sqrt{3*36}+ sqrt{6} =$$30 sqrt{3} -35 sqrt{3}-3 sqrt{3} -30 sqrt{3}+ sqrt{3 } sqrt{2} = -38 sqrt{3}+ sqrt{3} sqrt{2} =$$- sqrt{3} *(38- sqrt{2})$

2.     .........$=-5 sqrt{5} * frac{ sqrt{125}-1 }{ sqrt{5}+2 sqrt{20} } =-5 sqrt{5}* frac{5 sqrt{5}-1 }{ sqrt{5}(1+2 sqrt{4} ) } = -5 sqrt{5} * frac{5 sqrt{5}-1 }{5 sqrt{5} } =-5 sqrt{5}-1$

3.      .......$=4*3+ frac{9*3}{5}-6+ frac{4}{15}=12+5 frac{2}{5}-6+ frac{4}{15} =6+5 frac{10}{15}=11 frac{2}{3}$