Question

sin45+cos45 -sec90 what is the ans of it

Answer 1

sin45 =1/root2
cos45 = 1/root2
sec90= infinity
1/root2 + 1/root2 - infinity
2/root2 -infinity
root2 - infinity
1.414- Infinity
= - infinity is answer

Answer 2

Let me help you with this question.
Given that,
sin 45° . cos 45° - sin 300°
= (1 / √2) . (1 / √2) - sin 300° (∵sin 45° = cos 45° = 1 / √2)
= 1 / (√2 x √2) - sin (270° + 30°)   
= 1 / 2 - (- cos 30°)   [∵ sin (270° + ∅) = - cos ∅]
= 1 / 2 + cos 30° 
= 1 / 2 + √3 / 2  (∵ cos 30° = √3 / 2)
= (1 + √3) / 2 
which is the required answer.
Hope it will help you. Thanks.