Let f(x)= |x| and g(x)=x^2
Find all values of x for which f(x)>g(x)
To find all values of x for which f(x)>g(x), where f(x)=|x| and g(x)=x2, we need to compare their values for different ranges of x.
1. For x≥0:
f(x)=|x|=x
g(x)=x2
So, f(x)>g(x) for x≥0 when x2>x, which is true when x>1 or x<0.
2. For x<0:
f(x)=|x|=−x
g(x)=x2
So, f(x)>g(x) for x<0 when −x>x2, which is true when −x>x2 for x<0.
Let's solve −x>x2 for x<0:
−x>x2
x2+x<0
x(x+1)<0
This inequality holds true when either x<0 and x+1>0, or x>0 and x+1<0.
1. For x<0, x(x+1)<0 when x<0 and x+1>0 (the product of two negative numbers is positive):
x<0
x+1>0
x>−1
So, for x<0, f(x)>g(x) when −1<x<0.
Combining both ranges of x, we have f(x)>g(x) for x>1 or −1<x<0.
Therefore, all values of x for which f(x)>g(x) are x∈(−1,0)∪(1,∞).