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A bug is moving along the right side of the parabola y = x at a rate such that its distance from the origin is increasing at 9 cm/min. a. At what rate is the x-coordinate of the bug increasing when the bug is at the point (4, 16)? dy dx b. Use the equation y=x² to find an equation relating to dt dt c. At what rate is the y-coordinate of the bug increasing when the bug is at the point (4, 16)? 2 a. Let D=√x + y terms of only x. 4 2 D = √x +X Differentiate both sides of the equation with respect to t. dD dt 2 2x + 1 be the distance the bug is from the origin. Considering the bug is moving along y = x, rewrite D in 1 2 dx dt (x²+1) At what rate is the x-coordinate of the bug increasing when the bug is at the point (4, 16)? The x-coordinate of the bug is increasing at a rate of (Type an exact answer, using radicals as needed.)​

User Alfonz
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Answer:

Explanation:

a. To find the rate at which the x-coordinate of the bug is increasing when the bug is at the point (4, 16), we need to differentiate the equation y=x with respect to time t:

dy/dt = dx/dt

Since the bug is moving along the right side of the parabola y=x, the bug's position can be described by the equation y=x^2. Taking the derivative of both sides with respect to time t, we get:

2y(dy/dt) = 2x(dx/dt)

Simplifying and plugging in the given values for y and dy/dt:

2(16)(9) = 2(4)(dx/dt)

dx/dt = 36 cm/min

Therefore, the x-coordinate of the bug is increasing at a rate of 36 cm/min when the bug is at the point (4, 16).

b. The equation y=x^2 can be rewritten as x=sqrt(y). Differentiating both sides with respect to time t, we get:

dx/dt = 1/(2sqrt(y)) * dy/dt

Substituting y=16 and dy/dt=9, we get:

dx/dt = 1/(2sqrt(16)) * 9

dx/dt = 9/8 cm/min

c. We can use the same equation from part (a) to find the rate at which the y-coordinate of the bug is increasing when the bug is at the point (4, 16):

2y(dy/dt) = 2x(dx/dt)

Substituting y=16, x=4, and dx/dt=36, we get:

2(16)(dy/dt) = 2(4)(36)

Solving for dy/dt:

dy/dt = 18 cm/min

Therefore, the y-coordinate of the bug is increasing at a rate of 18 cm/min when the bug is at the point (4, 16).

d. Let D be the distance the bug is from the origin. We can use the Pythagorean theorem to relate D to x and y:

D^2 = x^2 + y^2

Substituting y=x^2, we get:

D^2 = x^2 + x^4

Taking the derivative of both sides with respect to time t, we get:

2D(dD/dt) = 2x(dx/dt) + 4x^3(dx/dt)

Simplifying and substituting x=4, dx/dt=36, and y=16:

2sqrt(16+16^2)(dD/dt) = 2(4)(36) + 4(4^3)(36)

Solving for dD/dt:

dD/dt = (836 + 44^3*36) / (2sqrt(16+16^2))

dD/dt = 72/(sqrt(17))

Therefore, the distance between the bug and the origin is increasing at a rate of 72/(sqrt(17)) cm/min when the bug is at the point (4, 16).

User Xstian
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