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At what point on the curve x = 3t² + 7, y = t³ - 3 does the tangent line have a slope of 1/2?

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Final answer:

To find the point where the tangent line has a slope of 1/2, you need to solve a quadratic equation derived from the derivative of the given curve. The point occurs when t = (1 + sqrt(5)) / 2.

Step-by-step explanation:

The slope of a curve at a point is equal to the slope of a straight line tangent to the curve at that point. To find the point where the tangent line has a slope of 1/2, we need to find the value of t that satisfies the equation.

First, differentiate the equations to find the derivative of x and y:

dx/dt = 6t

dy/dt = 3t^2 - 3

Next, substitute the values of dx/dt and dy/dt into the slope formula:

slope = (dy/dt) / (dx/dt) = (3t^2 - 3) / (6t) = 1/2

Simplify the equation:

3t^2 - 3 = (1/2) * 6t

6t^2 - 6 = 6t

6t^2 - 6t - 6 = 0

Finally, solve the quadratic equation to find the value of t:

t^2 - t - 1 = 0

Using the quadratic formula:

t = (1 + sqrt(5)) / 2

Therefore, the point on the curve where the tangent line has a slope of 1/2 is when t = (1 + sqrt(5)) / 2.

User Ali Gol Gol
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