Chapter 2 - Acute Angles and Right Triangles - Section 2.3 Finding Trigonometric Function Values Using a Calculator - 2.3 Exercises - Page 64: 47

False

$/sin$ 10$^{\circ}$ + $sin$ 10$^{\circ}$ = $sin$ 20$^{\circ}$ $\sin$ 10$^{\circ}$ $\approx$ 0.173648 Therefore: $\sin$ 10$^{\circ}$ + $\sin$ 10$^{\circ}$ $\approx$ 0.173648 + 0.173648 $\sin$ 10$^{\circ}$ + $\sin$ 10$^{\circ}$ $\approx$ 0.347296 $\sin$ 20$^{\circ}$ $\approx$ 0.342020 Therefore $\sin$ 10$^{\circ}$ + $\sin$ 10$^{\circ}$ $\ne$ $\sin$ 20$^{\circ}$