SOLUTION: How do you solve 2x^-2 - x^-1 - 1 = 0? I need to get rid of the negative exponents and then solve using the quadratic formula. I am not sure of how to do this.

Algebra ->  Exponents -> SOLUTION: How do you solve 2x^-2 - x^-1 - 1 = 0? I need to get rid of the negative exponents and then solve using the quadratic formula. I am not sure of how to do this.      Log On


   

Question 324887: How do you solve 2x^-2 - x^-1 - 1 = 0? I need to get rid of the negative exponents and then solve using the quadratic formula. I am not sure of how to do this.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Since x%5E%28-1%29=1%2Fx%5E1=1%2Fx and x%5E%28-2%29=1%2Fx%5E2, this means that 2x%5E%28-2%29+-+x%5E%28-1%29+-+1+=+0 can be rewritten as 2%2Fx%5E2-1%2Fx-1=0


Now multiply EVERY term by the LCD x%5E2 to get 2-x-x%5E2=0. From there, rearrange the terms to get -x%5E2-x%2B2=0 and multiply every term by -1 to get x%5E2%2Bx-2=0. I'll let you use the quadratic formula to solve.