Question

2 sin^ 2 63° +1+2 sin^ 2 27° 3 cos^ 2 17° -2+3 cos^ 2 73° =?​

Answer 1

Answer:

Step-by-step explanation:

Given,  

cos

2

17+cos

2

73

sin

2

63+sin

2

27

​

=

cos

2

(17)+(cos(90−17))

2

sin

2

63+(sin(90−63))

2

​

As we know

90−63=27

90−17=73

from (sin(90−63)=cos63, cos(90−17)=sin17,

Now,

cos

2

17+cos

2

73

sin

2

63+sin

2

27

​

=

cos

2

(17)+(cos(90−17))

2

sin

2

63+(sin(90−63))

2

​

=

cos

2

17+sin

2

17

sin

2

63+cos

2

63

​

   

=

1

1

​

=1               ∵sin

2

A+cos

2

A=1