In the isosceles ,

MATHEMATICS · Single correct · CBSE · Mathematics · Vector Algebra · Vector Algebra

Problem

In the isosceles

\triangle ABC

|\mathbf{AB}| = |\mathbf{BC}| = 8

, a point

E

divides

AB

internally in the ratio

1:3

, then the cosine of the angle between

\mathbf{CE}

and

\mathbf{CA}

is (where,

|\mathbf{CA}| = 12

) (1)

-\frac{3\sqrt{8}}{8}

(2)

\frac{3\sqrt{8}}{17}

(3)

\frac{3\sqrt{7}}{8}

(4)

-\frac{3\sqrt{8}}{17}