True. That method wouldn't work if the range had a number of the form (n+0.5)π in it, because the sign changes at every point with that form, but they are not roots.

Ricky

2005-12-11 11:23:54

Just don't forget to also state the function is continuous from [1.1, 1.2].

mathsyperson

2005-12-10 23:18:36

To show that there is a root between 1.1 and 1.2, just find the values of the functions at each of those points and show that there is a change of sign.

f(1.1) ≈ 0.23 f(1.2) ≈ -0.17

There is a change of sign, so a root must exist between the two.

Flowers4Carlos

2005-12-10 16:29:54

i was working on problem one in degree mode and my calculator kept spitting out positiive results even for very large values of x. then i switched over to radian mode and it worked! sometimes a lil trial and error will get you on the right track!