Объяснение: (V-кореньБ ^-знак степени)
3) =12+42V5 -2V5-5=7+40V5
4) =30*2-25V6+36V6-30*3=60+11V6-90= 11V6-30
5) =(V17)^2 -(V11)^2=17-11=6 по формуле: (a-b)(a+b)=a^2 -b^2)
6) =(2Vx)^2-(5Vy)^2=4x-25y
7) = (V6)^2-2*2*V6 +4=6-4V6 +4=10-4V6 [ (a-b)^2=a^2-2ab +b^2
8) =9*7 -2*3*2V21 -4*3 =51-12V21
Объяснение: (V-кореньБ ^-знак степени)
3) =12+42V5 -2V5-5=7+40V5
4) =30*2-25V6+36V6-30*3=60+11V6-90= 11V6-30
5) =(V17)^2 -(V11)^2=17-11=6 по формуле: (a-b)(a+b)=a^2 -b^2)
6) =(2Vx)^2-(5Vy)^2=4x-25y
7) = (V6)^2-2*2*V6 +4=6-4V6 +4=10-4V6 [ (a-b)^2=a^2-2ab +b^2
8) =9*7 -2*3*2V21 -4*3 =51-12V21