Question

No links please, i cant find the answer for q b) ii)

Answer 1

-k

Explanation:

Cos(140)=cos(180-40)=-cos(40)=-k

Answer 2

Explanation:

Sin (90 - A) = Cos A

Cos (90 + A) = -Sin A

Sin 50 = Sin (90 - 40)

= Cos 40

= k

Cos 140 = Cos (90 + 50)

= - Sin 50

= (- k)