Loading [MathJax]/jax/output/SVG/jax.js
 
+0  
 
+1
4290
3
avatar+647 

Find all real x where
2x5x3>2x5x+2+5.
Give your answer in interval notation.

 Mar 9, 2018
 #1
avatar+26396 
+4

Find all real x where

2(x5x3)>2x5x+2+5.
2\cdot\frac{x-5}{x-3} > \frac{2x-5}{x+2} + 5.

 

1. rearrange:

2(x5x3)>2x5x+2+52x10x3>2x5+5(x+2)x+22x10x3>2x5+5x+10x+22x10x3>7x+5x+2

 

2.  reduce / convert fractions to a common :

2x10x37x+5x+2>0(2x10)(x+2)(7x+5)(x3)(x3)(x+2)>02x2+4x10x207x2+21x5x+15(x3)(x+2)>05x2+10x5(x3)(x+2)>05(x22x+1)(x3)(x+2)>0|:(5) attention ">"→"<"x22x+1(x3)(x+2)<0|x22x+1=(x1)2(x1)2(x3)(x+2)<0|(x3)2(x+2)2(x1)2(x3)2(x+2)2(x3)(x+2)<0(x1)2(x3)(x+2)<0

 

3. solve the equation:

sign(,2)2(2,1)1(1,3)3(3,)x30+(x1)2+++0+++x+20+++++sign of (x1)2(x3)(x+2)+000+

 

interval notation: (2,1) and (1,3)

 

laugh

 Mar 9, 2018
 #2
avatar+647 
-1

im not sure thats correct

 Mar 10, 2018
 #3
avatar+33654 
+4

Heureka's result looks right to me:

 

.

Alan  Mar 10, 2018

1 Online Users