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:
x= -11/4 is a maximum.
Step-by-step explanation:
Remember that a function has its critical points where the derivative equal zero. Therefore we need to compute the derivative of this function and find the points where the derivative is zero. Using the chain rule and the product rule we get that
And then we get that if then
. So it has a critical point at
.
Now, if the second derivative evaluated at that point is less than 0 then the point is a maximum and if is greater than zero the point is a minimum.
Since
x= -11/4 is a maximum.