Cos 157.5º=-cos (180º-157.5º)=-cos 22.5=-cos(45/2)
cos Ф/2=⁺₋√((1+cosФ)/2).
In this case 157.5º is in the second quadrant, therefore we use the following equation:
cos Ф/2=-√((1+cosФ)/2). (we will have a negative number)
cos 157.5º=-cos (45/2)=-√((1+cos 45º)/2)
=-√((1+√2/2)/2)
=-√((2+√2)/4)
=-√(2+√2) / 2 (≈-0.92387...)
Answer: cos 157.5º= -√(2+√2) / 2
X=4
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Answer:
When all sides are equal
Step-by-step explanation:
The first step to solving this is to remember our mathematical rules. They state that when the term has a coefficient of -1,, the number doesn't have to be written but the sign needs to remain. This will change the expression to the following:
x - v + 4 + 7y - 3
Now subtract the numbers 4 and 3 from each other.
x - v + 1 + 7y
Since this expression cannot be simplified any further,, the correct answer to your question would be x - v + 1 + 7y.
Let me know if you have any further questions.
:)
