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# C1 Questions - Help needed. watch

1. Thanks all for helping, everything solved.
2. For the last bit of inequalities, I always sketch a graph with the two x values.
If the original inequality is >0 the values are when the graph goes above the x axis and if the original inequality is <0 the values are when the graph goes under the x axis.

This is because for >0 , the curve is more than 0 and when the curve goes above the x axis, it is above y=0, so it is more than 0 and it's the opposite for <0.

Idk if that's clear enough but it's how I learnt it.
3. Cancel off question 13 (ii) and (iii). Know how to do them, on the second paper.
4. (Original post by Dr. Swiftie)
For the last bit of inequalities, I always sketch a graph with the two x values.
If the original inequality is >0 the values are when the graph goes above the x axis and if the original inequality is <0 the values are when the graph goes under the x axis.

This is because for >0 , the curve is more than 0 and when the curve goes above the x axis, it is above y=0, so it is more than 0 and it's the opposite for <0.

Idk if that's clear enough but it's how I learnt it.
Omg yes. Now you clicked something in mind, I remember my teacher telling us that. Thanks.
5. (Original post by Slenderman)
Edit: How do you do the last bit of solving a quadratic inequality? I can get the two numbers but I just can't seem to work out whether they need to be < or >. If ya get what I mean.
Sketch the graph and identify where it is >0 and where it is <0.
6. for the 13 on the first paper, put it in to one equation and use a quadratic equation to show that there is a positive root
7. Yep I can do it now, thanks.
8. For 12iii on second what did you get in th a(x+b)^2-c equation?
9. (Original post by liverpool2044)
for the 13 on the first paper, put it in to one equation and use a quadratic equation to show that there is a positive root
Hmm I see so you use the quadratic formula on it. I will try this now.
10. (Original post by liverpool2044)
For 12iii on second what did you get in th a(x+b)^2-c equation?
I got 3(x+1)^2 +7
11. (Original post by liverpool2044)
for the 13 on the first paper, put it in to one equation and use a quadratic equation to show that there is a positive root
I used b^2 - 4ac and got k +/- square root k^2 + 8

Now what?
12. (Original post by Slenderman)
I got 3(x+1)^2 +7
Good, so you know the minimum point is going to have y coordinate 7 so its always going to be above the x axis
13. I see, that's so simple. The way they worded it made me confused. Thanks.
14. (Original post by Slenderman)
I used b^2 - 4ac and got k +/- square root k^2 + 8

Now what?
you know its going to have to be greater than 0 so put it into the quadratic formula so it applies to all values for k
15. (Original post by liverpool2044)
you know its going to have to be greater than 0 so put it into the quadratic formula so it applies to all values for k
Okay. So I got.. the same thing over 2. (I used b +/- square root b^2-4ac all over 2). Is this right so far?
16. k+ root k^2-8 is greater than or equal to zero for all values of k is what you need to say. This shows a positive root for x^2 and so an intersection.
17. I'm not doing C1 again. But what knowledge do you need for FP1?
18. Okay thanks everyone, everything is solved.

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