Q. Express as a function of a DIFFERENT angle, 0∘≤θ<360∘.cos(308∘)cos(□∘)
Understand concept reference angles: Understand the concept of reference angles. The reference angle is the acute angle that a given angle makes with the x-axis. It is always between 0∘ and 90∘ and can be used to find the cosine of the original angle because cosine is the x-coordinate on the unit circle.
Find reference angle 308°: Find the reference angle for 308°. Since 308° is in the fourth quadrant (where angles are between 270° and 360°), we subtract it from 360° to find the reference angle. Reference angle = 360°−308°=52°
Determine cosine reference angle: Determine the cosine of the reference angle.The cosine of an angle in the fourth quadrant is positive, and since the reference angle is 52∘, we have:cos(52∘)=cos(360∘−308∘)
Express cosine function: Express the original cosine function in terms of the reference angle.Since the cosine function is positive in the fourth quadrant, we can write:cos(308°)=cos(360°−52°)=cos(52°)
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