Объяснение:
h = h0+v0t-gt^2/2
a) 60 = 25+40t-5t^2
5t^2-40t+35=0
t^2-8t+7= 0
Д=64-28=36
t1 = 8+6/2=7с
t2 = 8-6/2=1с
Объяснение:
h = h0+v0t-gt^2/2
a) 60 = 25+40t-5t^2
5t^2-40t+35=0
t^2-8t+7= 0
Д=64-28=36
t1 = 8+6/2=7с
t2 = 8-6/2=1с