Answer with Step-by-step explanation:
We are given that

For each real number 
To prove that f is one -to-one.
Proof:Let
and
be any nonzero real numbers such that

By using the definition of f to rewrite the left hand side of this equation

Then, by using the definition of f to rewrite the right hand side of this equation of 

Equating the expression then we get




Therefore, f is one-to-one.
Answer:
Step-by-step explanation:
So there is a 3% probability that an athlete is using EPO .
The probability of showing positive on a test when you've used it is 0.99.
3% x 0.99= 2.97%
The probability of a positive result without EPO is 0.1
97% x 0,1 = 9,7 %
My guess is that 2.97% + 9,7% = 12.67% or 0.1267.
I don't know i may be wrong because you've put as an answer 0.0297 but if you like you may take only the first part of the answer.