Fungsi f: R→R dang: R→R . Jika g(x) = x−2 dan (fog)(x) = x²−4 nilai dari f(4) adalah.....

The notation $(f \circ g)(x)$ means $f(g(x))$.
We are given:

$$g(x) = x-2$$ $$(f \circ g)(x) = x^2 - 4$$

So, we can write:

$$f(g(x)) = x^2 - 4$$

Substitute $g(x) = x-2$ into the equation from Step 1:

$$f(x-2) = x^2 - 4$$

We want to find $f(4)$. This means the expression inside the parentheses for $f$ should be 4.
Let $x-2 = 4$.
Solving for $x$:

$$x = 4 + 2$$ $$x = 6$$

Substitute $x=6$ into $f(x-2) = x^2 - 4$:

$$f(6-2) = (6)^2 - 4$$ $$f(4) = 36 - 4$$ $$f(4) = 32$$

The value of $f(4)$ is 32.

Comparing this with the given options:
a. 32
b. 24
c. 12
d. 40
e. 38

The correct option is a.

The final answer is $\boxed{\text{a. 32}}$.