Problem 47 - Precalculus: A Concise Course

Question

Use a calculator to evaluate each function. Round your answers to four decimal places. (Be sure the calculator is in the correct angle mode.) (a) \(\sin 10^{\circ}\) (b) \(\cos 80^{\circ}\)

Step-by-Step Solution

Answer

The rounded values are \(\sin 10^{\circ} = 0.1736\) and \(\cos 80^{\circ} = 0.1736\).

Step 1: Set the Calculator to Degree Mode

Before starting the evaluations, make sure the calculator is in Degree mode rather than Radian mode.

Step 2: Evaluate \(\sin 10^{\circ}\)

To evaluate this, type 'sin(10)' into the calculator and press the equals button. The result will be the sine of 10 degrees, make sure to write down the result exactly as displayed.

Step 3: Round the Result

Round the result from Step 2 to four decimal places. Depending on the calculator, additional rounding steps might be necessary.

Step 4: Evaluate \(\cos 80^{\circ}\)

To evaluate this, type 'cos(80)' into the calculator and press the equals button. The result will be the cosine of 80 degrees, write down the result exactly as displayed.

Step 5: Round the Result

Round the result from Step 4 to four decimal places. Depending on the calculator, additional rounding steps might be necessary.