Without using a calculator, give the exact trigonometric function value with rational denominator.
-$\sec 30 ^ { \circ }$
A) $\sqrt { 2 }$
B) $\frac { 2 \sqrt { 3 } } { 3 }$
C) $\frac { 1 } { 2 }$
D) 1

Question

Quizplus · Accepted Answer

The secant function is the reciprocal of the cosine function. The cosine of 30 degrees is $\frac{\sqrt{3}}{2}$, so the secant of 30 degrees is the reciprocal, $\frac{2}{\sqrt{3}}$. Rationalizing the denominator gives $\frac{2\sqrt{3}}{3}$.

Without Using a Calculator, Give the Exact Trigonometric Function Value sec⁡30∘\sec 30 ^ { \circ }sec30∘

Without Using a Calculator, Give the Exact Trigonometric Function Value $\sec 30 ^ { \circ }$