Find the t such that 0 ≤ t ≤ π and cos t = cos $\left( - \frac { 2 \pi } { 3 } \right)$ .
A) $\frac { \pi } { 3 }$
B) - $\frac { \pi } { 3 }$
C) $\frac { 2 \pi } { 3 }$
D) $\frac { \pi } { 6 }$
E) none of these

Question

Quizplus · Accepted Answer

The cosine function is even, so cos(t) = cos(-t). Since cos(-2π/3) = cos(2π/3), and 2π/3 is within the range 0 ≤ t ≤ π, the correct answer is 2π/3.

Find the T Such That 0 ≤ T ≤ π (−2π3)\left( - \frac { 2 \pi } { 3 } \right)(−32π​)

Find the T Such That 0 ≤ T ≤ π $\left( - \frac { 2 \pi } { 3 } \right)$