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1. So basically I learnt a particular method of solving quad equations that my textbook doesn't use, so when I solve quadratic inequalities I get different critical values than the textbook? (Same numbers, different signs)

Are these two expressions the same?:
-3 < x < 1/3 (textbook)
3 > x > -1/3 (my answer)

The original inequality is 3x^2 + 8x - 3 < 0 if that makes a difference

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2. No they are different, once u have factorised it try drawing the lines (in this case y = 3x -1 and y = x + 3) and see for what x values will this inequality be negative.

Once the graph has been drawn you will be able to see that it's between -3 and 1/3
3. (Original post by hi-zen-berg)
So basically I learnt a particular method of solving quad equations that my textbook doesn't use, so when I solve quadratic inequalities I get different critical values than the textbook? (Same numbers, different signs)

Are these two expressions the same?:
-3 < x < 1/3 (textbook)
3 > x > -1/3 (my answer)

The original inequality is 3x^2 + 8x - 3 < 0 if that makes a difference

Posted from TSR Mobile
How could they be the same
And, of course 3+8-3 = 8 which is not <0

4. (Original post by MaloneJ)
No they are different, once u have factorised it try drawing the lines (in this case y = 3x -1 and y = x + 3) and see for what x values will this inequality be negative.

Once the graph has been drawn you will be able to see that it's between -3 and 1/3
(Original post by TenOfThem)
How could they be the same
And, of course 3+8-3 = 8 which is not <0

Ok thanks I reviewed it and I made a stupid mistake with signs, thanks

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