Question #5a205

2 Answers
Jan 4, 2018

-1 < x < 11<x<1

Explanation:

Start with: x^2<1x2<1

subtract 1 from both sides:

x^2-1<0x21<0

Factor the left:

(x-1)(x+1)<0(x1)(x+1)<0

Find the zeros of the left: x=-1x=1 and x=1x=1.

Create a sign chart for these numbers by testing in the factored form: (x-1)(x+1)(x1)(x+1). I tested x = -100x=100, x=0x=0, and x=100x=100

++++ (-1) ----- (1) +++++

from the sign chart we can see that (x-1)(x+1)<0(x1)(x+1)<0 on the interval -1 < x < 11<x<1 and that is the solution set.

If you're familiar with the graph of y=x^2y=x2 you can also graph it along with y=1y=1 and visually see the solution is where the parabola is less than the line, which is the interval -1 < x < 11<x<1.

Jan 4, 2018

Solution set is (-1,1) or,-1<-x<-11<x<1

Explanation:

It is a quadratic inequality. Consider intervals (-oo,-1), (-1,0),(0,1)and (1,oo)(,1),(1,0),(0,1)and(1,). In equality does not hold good in the intervals (-oo,-1) and (1,oo)(,1)and(1,)

By assigning any value to x in the intervals (-1,0) and (0,1), the inequality is found to be valid.
At x=0 also the Inequality holds good.

Thus, inequality holds good in the interval (-1,1). The solution set is thus (-1,1) or -1<-x<11<x<1