Help!!!!
\[x^{2} \ge 17\]
\[x^2-17\ge0\]
\[(x-\sqrt{17})(x+\sqrt{17})\ge0\]
Can you take it from there?
Can you help me go through it please. I'm having difficulty w/ problems like this :(
For the product to be greater than 0, both factors have to be positive or both factors have to be negative. Do you understand that?
no sorry
6(3) How many factors is that?
2
Are they both positive?
yes because bot numbers are positie
positive
Is the answer positive or negative?
positive
So I could write that : \[6(3)\ge 0\]
Would you agree?
yes
Also if both of my factors are negative as in (-6)(-3)
I would again get a positive answer and could write that: \[(-6)(-3)\ge0\]
However is one factor is negative and one positive as in: (-6)(3) or (6)(-3) then I could not truthfully write: \[(-6)(3)\ge0\]
So back to your problem. If \[(x-\sqrt{17})(x+\sqrt{17}\ge0\]
If that is true then both factors have to be negative or both factors have to be positive. Do you see that now?
kinda. so the answer should be \[\times \ge 17\]
So the usual technique is to draw a picture of each factor indicating where each is positive and each is negative.
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