Question

evaluate the following sin 45 degree sin 30 degree + cos 45 degree cos 30 degree​

Answer 1

Answer:

I hope it's correct

I am a student

Answer 2

Answer:

(√3+1)/2√2

Step-by-step explanation:

To evaluate,

sin 45 sin 30 + cos 45 cos 30

We know that,

• sin 45 = 1/√2
• sin 30 = 1/2
• cos 45 = 1/√2
• cos 30 = √3/2

Substituting the values,

Therefore, we will get,

= 1/√2 × 1/2 + 1/√2 × √3/2

= 1/2√2 + √3/2√2

= (1+√3)/2√2

= (√3+1)/2√2

Hence, the required value is (√3+1)/2√2.

Some trignometric values :-

• sin 0 = 0
• cos 0 = 1
• tan 0 = 0
• tan 30 = 1/√3
• tan 45 = 1
• sin 60 = √3/2
• cos 69 = 1/2
• tan 60 = √3
• sin 90 = 1
• cos 90 = 0
• tan 90 = ∞