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Math help pls i don’t understand how to solve this

Math help pls i don’t understand how to solve this-example-1

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Answer: y = x+1

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Step-by-step explanation:

f(x) = x^3 - 2x + 3

f ' (x) = 3x^2 - 2 ..... apply the power rule

f ' (1) = 3(1)^2 - 2 ... plug in x coordinate of given point

f ' (1) = 1

If x = 1 is plugged into the derivative function, then we get the output 1. This means the slope of the tangent line at (1,2) is m = 1. It's just a coincidence that the x input value is the same as the slope m value.

Now apply point slope form to find the equation of the tangent line

y - y1 = m(x - x1)

y - 2 = 1(x - 1)

y - 2 = x - 1

y = x - 1 + 2

y = x + 1 is the equation of the tangent line.

The graph is shown below. I used GeoGebra to make the graph.

Math help pls i don’t understand how to solve this-example-1
User Cayne
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