7x - x - 3 = 6x - 3
7x - x - 6x = -3 + 3
0 = 0
Ответ:
Объяснение:
!!!!!!!!!!!!!!!!!!!!!!!!!!!
dz/du=2f(cosu+cosv)*f'(cosu+cosv)*(cos'u+cos'v)=
=2f(cosu+cosv)*f'(cosu+cosv)*(-sinu)
ответ строчка 2)
А) 5 - ( a - 3) = 5 - a + 3 = 8 - a
Б) 7 + ( 12 - 2b) = 7 + 12 - 2b = 19 - 2b
В) 64 - ( 14 - 7x) = 64 - 14 + 7x = 50 + 7x
Г) 38 + ( 12p - 8) = 38 + 12p - 8 = 30 + 12p = 6 ( 5 + 2p)