Use the angle addition identity for cosine .e^(i Pi)+1=0 said:Homework Statement
If Sin(u)=[itex]\frac{\sqrt{2}}{2}[/itex] and cos(v)=[itex]\frac{4}{5}[/itex] and
0≤ u ≤[itex]\frac{∏}{2}[/itex] and [itex]\frac{3∏}{2}[/itex]≤ v ≤ 2∏
find cos (u+v)
The Attempt at a Solution
cos(u)=[itex]\frac{\sqrt{2}}{2}[/itex] and cos(v)=[itex]\frac{4}{5}[/itex]
Do I just add them together? I feel like I'm missing something, but maybe the problem really is that simple.
The formula for finding cos(u+v) is cos(u+v) = cos(u)cos(v) - sin(u)sin(v).
The steps for solving trig homework problems involving cos(u+v) are:
Finding cos(u+v) relates to the unit circle because it involves using the trigonometric functions (cosine and sine) to find the coordinates of a point on the unit circle. The value of cos(u+v) represents the x-coordinate of the point on the unit circle with a central angle of u+v.
Yes, you can use a calculator to find cos(u+v) for any values of u and v. However, make sure your calculator is set to the correct angle mode (degrees or radians) before entering the values.
One common mistake to avoid when solving problems involving cos(u+v) is forgetting to use the correct signs for cos(u) and sin(u) in the formula. Another common mistake is not using the correct angle mode (degrees or radians) on your calculator. It is also important to double check your calculations and make sure you are using the correct values for u and v.