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Find r(t) if r′(t)=6t^2i+e^2tj+sintk and r(0)=3i−2j+k.

User PBulls
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Answer:

r(t) = (2t^3 + 3)i + (1/2 e^2t - 2)j + (-cos(t) + 4)k

Explanation:

Given r′(t)=6t^2i+e^2tj+sintk and r(0)=3i−2j+k.

To find r(t), we need to integrate r′(t). Integrating each component of r′(t), we get:

r(t) = ∫ r′(t) dt = ∫ (6t^2i+e^2tj+sintk) dt

Integrating the x-component, we get:

∫ 6t^2 dt = 2t^3 + C1

Integrating the y-component, we get:

∫ e^2t dt = 1/2 e^2t + C2

Integrating the z-component, we get:

∫ sin(t) dt = -cos(t) + C3

where C1, C2, and C3 are constants of integration.

Therefore, the solution for r(t) is:

r(t) = (2t^3 + C1)i + (1/2 e^2t + C2)j + (-cos(t) + C3)k

Using the initial condition, r(0)=3i−2j+k, we can find the values of the constants of integration:

r(0) = (2(0)^3 + C1)i + (1/2 e^2(0) + C2)j + (-cos(0) + C3)k

Simplifying, we get:

C1 = 3

C2 = -2

C3 = 4

Therefore, the final solution for r(t) is:

r(t) = (2t^3 + 3)i + (1/2 e^2t - 2)j + (-cos(t) + 4)k

User Laura Calinoiu
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