Answer:
Step-by-step explanation:
If air resistance is neglected, the energy is constant. That means that in every point in the trajectory the energy is the same.
At the point of height h, all the energy is potential and velocity is zero (no kinetic energy)
At point of height h/4, some of the potential energy has transformed in kinetic energy and the velocity is no longer zero. But we know the total amount of energy is the same as the maximum height point.
With that information, we can calculate the velocity v:
Answers are: A, C, D
Note how
(3/20)*20 = 0.15*20 = 3
0.15*20 = 3
(15/100)*20 = 0.15*20 = 3
all expressions lead to the same result of 3
another thing to notice
3/20 = 15/100 = 0.15 = 15%
which are multiple ways to say the same thing just in a different form
We can solve this problem using discriminant.
x^2-4x-12's discriminant is
(-4)^2-4*-12=16+48 which is clearly larger than 0
This means that it crosses over the axes 2 times.
In case you don't know what discriminant is, its in equation ax^2+bx+c
the discriminant is b^2-4ac.
If its positive it has 2 crosses with x axis, if negative then 0 crosses, if 0 then 1 cross.
Hope this helped at least a little bit :D
Answer:
The bottom right.
Step-by-step explanation:
Hope its correct.
Answer:
C.1/2
Step-by-step explanation:
