Intermediate Value Theorem...2

[nycmathguy]

Section 2.2
Example 6

Look at EXAMPLE 6. How do I divide the interval
[-1, 0] into tenths to get f(-0.8) = -0.152 and f(-0.7) = 0.167? Where did x = -0.8 and x = -0.7 come from?

 

[MathLover1]

[-1, 0] is divided into tenths

from -1 to 0 tenths are
-10/10,-9/10,-8/10,-7/10,-6/10,-5/10,-4/10,-3/10,-2/10,-1/10

so -8/10=-0.8 and -7/10=-0.7 are assumed to be ones that have zero between

evaluation shows that f(-0.8)=0.152 and f(-0.8)=0.167 which is rounded pretty close to zero, so real zero will be somewhere between

and calculation shows that real zero is approximately x=-0.755

 

[nycmathguy]

[-1, 0] is divided into tenths

from -1 to 0 tenths are
-10/10,-9/10,-8/10,-7/10,-6/10,-5/10,-4/10,-3/10,-2/10,-1/10

so -8/10=-0.8 and -7/10=-0.7 are assumed to be ones that have zero between

evaluation shows that f(-0.8)=0.152 and f(-0.8)=0.167 which is rounded pretty close to zero, so real zero will be somewhere between

and calculation shows that real zero is approximately x=-0.755

Thank you for explaining this to me.