Implicit Differentiation Integral Involution
1. Problem: Find $\frac{dy}{dx}$ if $x + y^4 = 10$ and $y \neq 0$.
2. Differentiate both sides with respect to $x$:
$$\frac{d}{dx}(x) + \frac{d}{dx}(y^4) = \frac{d}{dx}(10)$$
This gives:
$$1 + 4y^3 \frac{dy}{dx} = 0$$
3. Solve for $\frac{dy}{dx}$:
$$4y^3 \frac{dy}{dx} = -1$$
$$\frac{dy}{dx} = \frac{-1}{4y^3}$$
4. Therefore, the correct option is (A) $\frac{-1}{4y^3}$.
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5. Problem: If $h(x) = \int_0^{x^2} g(t) dt$, find $h'(x)$.
6. Using the Fundamental Theorem of Calculus and chain rule:
$$h'(x) = g(x^2) \cdot \frac{d}{dx}(x^2) = g(x^2) \cdot 2x = 2x g(x^2)$$
7. The correct option is (C) $2x g(x^2)$.
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8. Problem: Given $f(f(x)) = x$, which graph could represent $f$?
9. Explanation: The condition $f(f(x)) = x$ means $f$ is an involution and its own inverse. The graph of $f$ must be symmetric about the line $y = x$.
10. Option (D) describes a function resembling a hyperbola with branches in the first and third quadrants, which is symmetric about $y=x$.
11. Therefore, option (D) is the correct graph for $f$.
Final answers:
1) $\frac{dy}{dx} = \frac{-1}{4y^3}$
2) $h'(x) = 2x g(x^2)$
3) Graph: option (D)