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Thansi
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The function f is defined by f(x) = 8-2(x-4) ^2. The graph of y=f(x) intersects the x-axis at A and B. Determine the equation of the tangent at B using differentiation. How to solve this?
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Tgm11801
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So what do you need to find the equation of a line? Y=mx+c. And you need to know B, how do you first x-axis intercepts/roots?
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RDKGames
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(Original post by Thansi)
The function f is defined by f(x) = 8-2(x-4) ^2. The graph of y=f(x) intersects the x-axis at A and B. Determine the equation of the tangent at B. How to solve this?
Kind of an ambiguous questions considering you don't know which root corresponds to A and which root corresponds to B.
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the bear
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should be in Relationships....

wait :facepalm2:
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thotproduct
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As RDK said, the question is ambiguous in the definition of roots A and B, is there more information in the question that you haven't mentioned? A condition on one of the roots being above a certain number?

Your general plan here regardless, is to solve f(x) = 0, to find the two points where it intersects the x-axis, one of those x values will correspond to the root B. Then differentiate the function and substitute that value of x to get the gradient of the tangent. Your coordinates are (B,0), how do you find the equation of a line given the gradient, and coordinates that it passes through?
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Thansi
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(Original post by Thansi)
The function f is defined by f(x) = 8-2(x-4) ^2. The graph of y=f(x) intersects the x-axis at A and B. Determine the equation of the tangent at B using differentiation. How to solve this?
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Thansi
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(Original post by RDKGames)
Kind of an ambiguous questions considering you don't know which root corresponds to A and which root corresponds to B.
Sorry, there were an error in uploading image of the full question.
Thanks for helping me.
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