Question

Evaluate the following - Cos 60 degree Cos 30 degree + Sin 60 degree Sin 30 degree​

Answer 1

Answer:

1/2*√3/2 + √3/2+1/2

=√3/4+√3/4

=2√3/4

=√3/2

Answer 2

$\huge \underline{ \underline{ \bf \purple{Solution :}}}$

$\longrightarrow \: \sf \cos60 \cos30 + \sin60 \sin30 \\ \\ \longrightarrow \: \sf \frac{1}{2} \times \frac{ \sqrt{3} }{2} + \frac{ \sqrt{3} }{2} \times \frac{1}{2} \\ \\ \longrightarrow \: \sf \frac{ \sqrt{3} }{4} + \frac{ \sqrt{3} }{4} \\ \\ \longrightarrow \: \sf \frac{ \sqrt{3} + \sqrt{3} }{4} \\ \\ \longrightarrow \: \sf \frac{2 \sqrt{3} }{4} \\ \\ \longrightarrow \: \sf \frac{ \sqrt{3} }{2}$