Solving inequalities

Jun 2012
15
0
Pakistan
This is very helpful but i am still stuck on a particular inequality. 2-3x<|x-3|. So far i have used the modular property and obtained a three term quadratic equation which further factorizes to (2x+1)(4x-5)<0. So according to me the answer is -1/2<x<5/4 but according to the marking scheme its only x>-1/2. Can somebody plz explain why?
 
Dec 2012
2
0
India
I was completely surprised by seeing all these meshes especially the triparts insert mesh.
 
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May 2013
4
0
Romania
Hello!
Solve the inequality \(\displaystyle 3x^2+4ix+5<0\) , where \(\displaystyle i^2=-1\).
Thank You!
 
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Sep 2013
29
0
south africa
I have trouble solving inequalities especially quadratic. My main problem is presenting critical points. I hope you attachment will solve my problem. Thank you
 
May 2013
4
0
Romania
I have trouble solving inequalities especially quadratic. My main problem is presenting critical points. I hope you attachment will solve my problem. Thank you
Any inequality can be written as an equation and so \(\displaystyle ax^2+bx+c\leq 0\) you can write the equation as \(\displaystyle ax^2+bx+c=d\leq 0\).The solutions of the inequality are :

\(\displaystyle x=\frac{-b\pm \sqrt{b^2-4a(c-d)}}{2a}\) where \(\displaystyle d\leq 0\).
 
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