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Help needed on equations and tangents to curve (1 Viewer)

Petinga

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I am given the straight line y=x+2 cuts the parabola y=1/2x squared -2 at points P and Q.


How do i find the coordinates of P and Q????????
 

nick1048

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solve the equations simultaneously i.e.

x + 2 = (1/2x)^2 - 2
x + 2 = (1/4x^2) - 2
4x^3 + 8x^2 = 1 - 8x^2
4x^3 + 16x^2 - 1= 0
4x^2(x + 4) - 1= 0
find the roots... you'll have 2 x values, those are your x values for P and Q
then sub those x values into any equation to find the y values :)

goodluck

... I think I read the question wrong but the method you use to solve these things is simultaneous equations.

please word this question again using ^2 where you want to indicate a squared operation btw this is not a parabola :)
 
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