Given:
There are given that the cos function:

Explanation:
To find the value, first, we need to use the half-angle formula:
So,
From the half-angle formula:

Then,
Since 105 degrees is the 2nd quadrant so cosine is negative
Then,
By the formula:

Then,
Put the value of cos210 degrees into the above function:
So,

Final answer:
Hence, the value of the cos(105) is shown below:
Hey there :)
- tan²x + sec²x = 1 or 1 + tan²x = sec²x
sin²x + cos²x = 1
Divide the whole by cos²x


so

and

so

Therefore,
tan²x + 1 = sec²x
Take tan²x to the other side {You will have the same answer}
1 = - tan²x = sec²x or sec²x - tanx = 1
Answer:
y=3x -6
Step-by-step explanation:
3=9+b
b= -6
Plural for index you are wecome bud
2. 12 3. 15. 5. 8. Those the answers hope that can help