i dont have the asnwer to this polynomial q, what is it (1 Viewer)

A1La5

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Using DESMOS the point G is . The other intersection point of the two graphs is not valid in this case as at this point the graph of cuts through the graph of (In layman terms a tangent is a line that just touches a curve at one point, rather than slicing through it). At the point the tangent line just touches the graph of , which matches the definition of what a tangent is.

In an exam situation it would be best to draw both of the graphs and to then determine which of the two intersection points is the right one.
 

CM_Tutor

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In an exam, you would be expected to say that the condition for the tangent to meet the curve is


This cubic equation must have three roots, but because the line is a tangent to the curve, the -coordinate of that point (and hence the corresponding solution to the cubic) must be a double root. Thus, let the cubic equation have roots and apply root theory to deduce that and .
 

yashbb

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In an exam, you would be expected to say that the condition for the tangent to meet the curve is


This cubic equation must have three roots, but because the line is a tangent to the curve, the -coordinate of that point (and hence the corresponding solution to the cubic) must be a double root. Thus, let the cubic equation have roots and apply root theory to deduce that and .
yep got it correct thank you so muchhhhh
 

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