Loading [MathJax]/jax/output/SVG/jax.js
 
+0  
 
0
870
4
avatar

Hey, I'm studying for a test on Wednesday. Would I be able to cancel out the "^16" in this equation to get ((x+1)^16)/x^16 = 1?

 Apr 17, 2017
 #1
avatar+130466 
+1

No....we can't do that.....

 

We have

 

(x + 1)^16 / x^16  =  1          multiply bothsides by x^16

 

(x + 1)^16   =  x^16             subtract x^16 from both sides

 

(x + 1)^16  - x^16   = 0             we can factor this several times, as follows

 

[  ( x + 1)^8  + x^8 ]  [ (x + 1)^8 - x ^8]   = 0

 

The first factor won't  have a real solution.....so.....working with the second

 

[ (x + 1)^4  + x^4]  [ (x + 1)^4 - x^4]  = 0

 

Again, the first has no real solution.....factor the second

 

[ ( x+ 1)^2  + x^2] [ (x + 1)^2 - x^2]  = 0 

 

No real solution for the first.......factor the second one more time

 

[ ( x + 1) + x]  [ (x + 1) - x ]  = 0

 

The second has no real solution......set the first to 0

 

(x + 1) + x  = 0     subtract 1 from both sides

 

2x  = -1        divide both sides by 2

 

x  = -1/2        this is the only real solution    

 

 

cool cool cool   

 Apr 17, 2017
 #2
avatar
0

I'm not trying to solve for x. Sorry, should've mentioned that. This is for a problem as x goes to infinity. I was able to solve it but I'm not sure if my reasoning was correct. I figured that (x+1)^16/x^16 the numerator and denominator have the same degree so when you use lhopitals rule the value approaches 1. Is this correct?

Guest Apr 18, 2017
 #3
avatar
0

The short answer is YES!

lim_(x->∞) (x + 1)^16/x^16 = 1

 Apr 18, 2017
 #4
avatar+26396 
0

Hey, I'm studying for a test on Wednesday.

Would I be able to cancel out the "^16" in this equation to get lim_(x->∞) (x + 1)^16/x^16 = 1?

 

limx(x+1)16x16=limx(160)x16+(161)x15+(162)x14++(1615)x1+(1616)x16=limx1x16+16x15+120x14++16x+1x16=limxx16x16+16x15x16+120x14x16++16xx16+1x16=limx1+16x+120x2++16x15+1x16=1+0+0++0+0=1

 

laugh

 Apr 18, 2017

3 Online Users