How do you evaluate #sec((11pi)/2)#? Trigonometry Right Triangles Trigonometric Functions of Any Angle 1 Answer Nghi N. · Nghi N Feb 16, 2017 undefined infinity Explanation: #sec ((11pi)/2) = 1/cos ((11p)/2)# #cos ((11pi)/2) = cos ((3pi)/2 + (8pi)/2) = cos ((3pi)/2 + 4pi) = # #= cos ((3pi)/2) = 0# Finally: #sec ((11pi)/2) = 1/(cos) = 1/0 #--> undefined infinity Answer link Related questions How do you find the trigonometric functions of any angle? What is the reference angle? How do you use the ordered pairs on a unit circle to evaluate a trigonometric function of any angle? What is the reference angle for #140^\circ#? How do you find the value of #cot 300^@#? What is the value of #sin -45^@#? How do you find the trigonometric functions of values that are greater than #360^@#? How do you use the reference angles to find #sin210cos330-tan 135#? How do you know if #sin 30 = sin 150#? How do you show that #(costheta)(sectheta) = 1# if #theta=pi/4#? See all questions in Trigonometric Functions of Any Angle Impact of this question 5134 views around the world You can reuse this answer Creative Commons License