Question down here or up cant really see if cant see tell me or not​

Factor k2 - 17k + 16. a.(k - 2)(k - 8) b.(k - 1)(k + 16) c.(k - 1)(k - 16)

Cos^2x+cos^2(120°+x)+cos^2(120°-x)i need this asap. pls me

Apolynomial has two terms. check all of the factoring methods that should be considered. common factor difference of cubes sum of cubes difference of squares perfect-square trinomial factoring by grouping