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# Pure Maths Proove that Question watch

1. Prove that, for all values of x,
x^2 +6x+18>2-1/2x
2. move all the terms to the left. then find the minimum point of the function on the LHS. if the y value is positive you have proved what was needed.
alternatively you can work with the discriminant of the LHS... if it is negative you have proved what is needed.
3. What are those blocks?

Is the problem:

x^2 + 6x + 18 > 2-0.5x?

--> x^2 + 6.5x + 16 > 0. This has no solutions as b^2-4ac>0 or you can evaluate the minimum point to be positive, etc.
4. (Original post by the bear)
move all the terms to the left. then find the minimum point of the function on the LHS. if the y value is positive you have proved what was needed.
alternatively you can work with the discriminant of the LHS... if it is negative you have proved what is needed.

Using b^2-4ac I found that it =-21.75
Is this right? Is that all I have to do?

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