a)
(-2/5)⁷×(+2/5)⁸:(-4/25)⁷=
=-(2¹⁵/5¹⁵) :(-2¹⁴/5¹⁴)=
=-(2¹⁵/5¹⁵) ×(-5¹⁴/2¹⁴)=
=2/5
b)0,1(6)×√0,36-60/√12+√300+√7×(1/√7+√7)=
0,1(6)=(16-1)/90=15/90=1/6
=1/6×0,6-60/2√3+10√3+1+7=
=1/6×6/10-60√3/6+10√3+8=
=1/6×6/10-10√3+10√3+8=
=1/10+8=
=(1+80)/10=
=81/10=
=8,1
=8,1+9√3
