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# quick maths q watch

1. If it says prove a curve has no turning points when they give you its forumula

and you differentiate it and say you get 3x^2 + 2,

to show it has no turning points is all you do just put a line through an equal sign and put 0 next to it i.e 3x^2 + 3 not equal to 0

or is there some mathematical way of proving it?!

this is for a/o maths tommorow
2. Your reasoning is fine, but I'd recommend you write it a bit clearer than that. Write a sentence like "3x^2 + 2 is nonzero for all real values of x, so the gradient of the curve is never 0 and hence there are no turning points".
3. Ok, so dy/dx= 3x^2+2

At turning points or stationary points, dy/dx=0

so... 3x^2 + 2 = 0
3x^2 = -2
x^2 = -2/3
x = square root of -2/3

but you cant square root a negative number because square numbers are always positive...so there are no solutions for dy/dx=0 therefore no stationary points
4. Thanks So much!

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