3.3=3 since the denominator is greater than the numerator
(f∘g)(x) is equivalent to f(g(x)). We solve this problem just as we solve f(x). But since it asks us to find out f(g(x)), in f(x), each time we encounter x, we replace it with g(x).
In the above problem, f(x)=x+3.
Therefore, f(g(x))=g(x)+3.
⇒(f∘g)(x)=2x−7+3
⇒(f∘g)(x)=2x−4
Basically, write the g(x) equation where you see the x in the f(x) equation.
f∘g(x)=(g(x))+3 Replace g(x) with the equation
f∘g(x)=(2x−7)+3
f∘g(x)=2x−7+3 we just took away the parentheses
f∘g(x)=2x−4 Because the −7+3=4
This is it
g∘f(x) would be the other way around
g∘f(x)=2(x+3)−7
now you have to multiply what is inside parentheses by 2 because thats whats directly in front of them.
g∘f(x)=2x+6−7
Next, +6−7=−1
g∘f(x)=2x−1
Its a lts easier than you think!
Hope this helped
are the critical points, and judging by the picture alone, you must have
and
. (You might want to verify with the derivative test in case that's expected.)
Then the shaded region has area
I'll leave the details to you.
Now, for part (iv), you're asked to find the minimum of
, which entails first finding the second derivative:
setting equal to 0 and finding the critical point:
This is to say the minimum value of
*occurs when
*, but this is not necessarily the same as saying that
is the actual minimum value.
The minimum value of
is obtained by evaluating the derivative at this critical point:
