Answer: option D
Step-by-step explanation:
Remember the cosine identity:
Given the right triangle DFE shown in the image, you can identify that the adjacent side and the hypotenuse for the angle F of this triangle are:
Now you can substitute values into and then reduce the fraction.
THerefore you get:
Answer:
Step-by-step explanation:
The formula is given as:
We need to solve this formula for v, that means that v to one side and let it be solved in terms of the other variables (E and m). First, we isolate v:
To isolate v, and eliminate the "square", we need to take square roots of both sides, that will give us v in terms of the other variables:
Putting v to left side (convention), we finally have:
