Question

find the value of sin square 30 degree + cos square 60 degree

Answer 1

Sin sq 30= 1/2 x 1/2 = 1/4
Cos sq 60= 1/2 x 1/2= 1/4

1/4 + 1/4 = 2/4= 1/2

Answer 2

Answer:

Value of the given expression is 1.

Step-by-step explanation:

Given,

sin square 30 degree + cos square 60

${sin}^{2} ( {30}^{o} ) + {cos}^{2}( {60}^{o} )$

We know,

$sin( {90}^{o} - x) = \cos(x) \\ and \cos( {90}^{o} - x) = \sin(x)$

From given expression,

${sin}^{2} ( {90}^{o} - {60}^{o} ) + {cos}^{2} {60}^{o} = {cos}^{2} {60}^{o} + {cos}^{2} {60}^{o} = 2 \times {cos}^{2} {60}^{o} = 2 \times ( \frac{1}{2} ) = 1$

So value of the given expression is 1.

List of degree values of sin and cos,

$Sin0°=0 \\ sin30°= \frac{1}{2} \\ sin45= \frac{1}{ \sqrt{2} } \\ \sin( {60}^{o} ) = \frac{ \sqrt{3} }{2} \\ \sin( {90}^{o} ) = 0$

and

$cos0°=0 \\ cos30°= \frac{1}{2} \\ cos45= \frac{1}{ \sqrt{2} } \\ \cos( {60}^{o} ) = \frac{ \sqrt{3} }{2} \\ \cos( {90}^{o} ) = 0$