f'(sinx)=cos^2x,f'(1)=1 then f(x)=
11 years ago
11 years ago
remember to add the constant of integration to that solution.
![Explain Bot](/images/users/4931/128x128.jpeg)
7 months ago
To find the function f(x), we need to integrate its derivative f'(x) with respect to x. Let's begin by integrating f'(sin(x)) = cos^2(x).
Integrating f'(sin(x)) with respect to x, we can use the substitution method. Let u = sin(x), then du = cos(x) dx. Rearranging, dx = du / cos(x).
Replacing dx and sin(x) in terms of u, we have:
∫f'(sin(x)) dx = ∫(cos^2(x)) dx
∫f'(u) du/cos(x) = ∫(cos^2(x)) dx
Since cos^2(x) = 1/2(1 + cos(2x)), we can rewrite the equation as:
∫f'(u) du/cos(x) = ∫(1/2)(1 + cos(2x)) dx
Expanding the integral on the right-hand side:
∫f'(u) du/cos(x) = ∫(1/2) dx + ∫(1/2)cos(2x) dx
The first integral on the right-hand side is ∫(1/2) dx = 1/2 x + C1, where C1 is the constant of integration.
For the second integral, we can use the substitution method again. Let w = 2x, then dw = 2 dx. Rearranging, dx = dw / 2.
Replacing dx and cos(2x) in terms of w, we have:
∫(1/2)cos(2x) dx = ∫(1/2)cos(w) (dw/2) = (1/4) ∫cos(w) dw
Integrating (1/4) ∫cos(w) dw = (1/4) sin(w) + C2, where C2 is the constant of integration.
Substituting the integral back into the equation, we get:
∫f'(u) du/cos(x) = 1/2 x + (1/4) sin(w) + C1
Since u = sin(x) and w = 2x, we can replace them back into the equation:
∫f'(sin(x)) du/cos(x) = 1/2 x + (1/4) sin(2x) + C1
Finally, to solve for f(x), we can integrate both sides with respect to x:
∫f'(sin(x)) du/cos(x) dx = ∫ (1/2 x + (1/4) sin(2x) + C1) dx
Integrating the left-hand side:
∫f'(sin(x)) du/cos(x) dx = ∫ du
Since f'(1) = 1, the left-hand side simplifies to:
f(u) + C3 = u + C3
Replacing u with sin(x) and simplifying further, we obtain:
f(x) = sin(x) + C3
Therefore, the function f(x) is f(x) = sin(x) + C3, where C3 is the constant of integration.