Please help me with this one.

Show that x^2 + 3x + 5 > 0, for all values of x.

and

Show that 2x^2 + 6 > 4x + 1, for all values of x.

How do i show it,????

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- Dec 27th 2008, 04:25 AMmazy22aquadratic equation
Please help me with this one.

Show that x^2 + 3x + 5 > 0, for all values of x.

and

Show that 2x^2 + 6 > 4x + 1, for all values of x.

How do i show it,???? - Dec 27th 2008, 04:35 AMmathaddict
- Dec 27th 2008, 04:36 AMmr fantastic
- Dec 27th 2008, 04:42 AMmazy22acheers
- Dec 27th 2008, 04:55 AMmr fantastic
How do you propose to draw the graph?

**Not**the lazy way - using a graphics calculator - I hope.

To draw the graph**by hand**(which is what you should be attempting to do) you need to calculate the x-intercepts. Use the quadratic formula to solve x^2 + 3x + 5 = 0. What do you notice about the discriminant ....? Therefore ..... - Dec 27th 2008, 05:11 AMmazy22a