1. I was asked how many zeros need to exist in order for the following functions to exist.

a) linear

Mr F says: No zeros needed for existence. Eg. The horizontal line y = 3.
b) quadratic

Mr F says: No zeros needed for existence. Eg. .
c) cubic

Mr F says: At least one zero needed for existence. All cubics approach +oo and -oo => must cut x-axis at least once.
d) quartic

Mr F says: No zeros needed for existence. Eg. .
e) quintic

Mr F says: At least one zero needed for existence. Same argument as cubic.
My answer would be none, but can anyone tell me if i am right?

Mr F says: No. See above.
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