Without using a calculator, decide whether the function value is positive or negative. (Hint: Consider the radian measures of the quadrantal angles.)cos2Is the value of the function cos2 positive or negative?positivenegative
Q. Without using a calculator, decide whether the function value is positive or negative. (Hint: Consider the radian measures of the quadrantal angles.)cos2Is the value of the function cos2 positive or negative?positivenegative
Recognize interval for 2 radians: Step 1: Recognize the interval for 2 radians. 2 radians is slightly more than π (which is approximately 3.14), so 2 radians falls between 0 and π/2.
Determine sign of cosine function: Step 2: Determine the sign of the cosine function in this interval. The cosine function is positive in the first quadrant 0 to π/2.
Cosine of 2 radians: Step 3: Since 2 radians is in the first quadrant, the cosine of 2 radians is positive.
More problems from Coterminal and reference angles