Cos 5pi 4

Determine the correct value, if specified: arccos (cos [5pi / 4])? 3

The solution is 3pi / 4. Explain in detail.

update

Thank you both.

So arcus means the angle is white cosine.

But first we work on the expression in square brackets: (cos [5pi / 4])

5 * pi / 4 is converted to degrees East (5 * 180) / 4 = 900/4 = 225 degrees, and this is in Quadrant III. Becomes

The cosine variable is similar to x and therefore this secondary answer will be negative, so (cos (225)) = SQ (2) / 2

Now we define the inside of the g square bracket: The global expression now looks like this:

Archos (square (2) / 2)

The angle that is the cosine of SQ (2) / 2 is 225 degrees or 135 degrees, which is 3pi / 4 in radians, so choose a smaller number.

Draw the circle of the unit.

The 5 ft / 4 angle is 1.25 ft, ahead of 0.25 ft. In Quadrant III.

Its cosine (vs. / hip) is a negative number because there are different signs of opposite directions and hyenas.

The ■■■■■■■ range is from 0 to pi. So you need to find an angle in this area that is equal to 5 cos / 4 cosine. The same negative number.

In your picture, you can see that this is an angle of 0.25 feet per foot (in Quadrant II). (0.25 feet from the X axis).

This angle will be 25 feet or 0.75 feet (3/4) feet or 3 feet / 4.

Cos 5pi 4