Question

sin 25 degree by 65 degree + cos 25 degree by cos 65 degree find the value without using trigonometric tables​

Answer 1

Answer:

sin25/sin 65+cos25/cos65

now,

sin (90-65)/sin65+cos(90-65)/cos65

=cos65/sin65+sin65/cos65

=cos65+tan65

=1/tan65+tan65

=1