can u help me with this math problem??

Question

1/f = 1/f1 + 1/f2 + 1/f3

solve for f1

I just need some help setting it up.

Answer 1

First, get F1 on its own private side of the equals. Do that by subtracting all the rest of the stuff from both sides, giving:
1/f - 1/f2 - 1/f3=1/f1. Now invert both sides giving:
1 / (1/f - 1/f2 - 1/f3) = f1. It is correct, but I'll admit is the ugliest solution I have seen this month.