Question

va rog!! Calculati : ( COROANA)!
1) (√15-3)( 3√5+ 4√3)(√5-√3)
2) 0,125- ( 9/√3 -2√3) : 8/√3

Answer 1

1) (√15-3)( 3√5+ 4√3)(√5-√3)=
=(3√75-9√5+ 4√45-12√3)(√5-√3)=
=(15√3-9√5+ 12√5-12√3)(√5-√3)=
=(3√3+3√5)(√5-√3)=
=3(√3+√5)(√5-√3)=
=3(√5+√3)(√5-√3)=
=3(5-3)=
=3×2=6

2) 0,125- ( 9/√3 -2√3) : 8/√3=
=125/1000-( 9/√3 -2√3) × √3/8=
=1/8-( 9/8 -6/8)=
=1/8-3/8=
=-2/8=-1/4