Question

(7la a 3a):(2la a 3a --1 la a3a)--2x(9 la a3a+1 la a4a :la 10 la a8a)=

Answer 1

(7^3):(2^3-1^3)-2x(9^3+10^4 :10^8)=
=(7^3):(8-1)-2x(3^6+1/10^4)=
=(7^3):7-2x(3^6+1/10^4)=
=49-2x(729+1/10000)=
=49-1458-1/5000)=
=-1409-1/5000=
=(-7045000-1)/5000=
=7045001/50000=
=1409,0002