Problem

Use the following information to answer the next question
Chantal simplified the expression $\frac{\csc \theta+\sec \theta}{\sin \theta+\cos \theta}$ as shown below.
\begin{tabular}{|c|c|}
\hline Steps & Simplification \\
\hline 1 & $\frac{\frac{1}{\sin \theta}+\frac{1}{\cos \theta}}{\sin \theta+\cos \theta}$ \\
\hline 2 & $\frac{\frac{\cos \theta+\sin \theta}{\sin \theta}}{\sin \theta+\cos \theta}$ \\
\hline 3 & $\left(\frac{\cos \theta+\sin \theta}{\sin \theta}\right)\left(\frac{1}{\sin \theta+\cos \theta}\right)$ \\
\hline 4 & $\frac{1}{\sin \theta}$ \\
\hline 5 & $\sec \theta$ \\
\hline
\end{tabular}
19. At what step did Chantal make her first mistake?
3
2
4
5

Answer

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Answer

Final Answer: \(\boxed{2}\)

Steps

Step 1 :The first step is correct, as \(\csc \theta\) and \(\sec \theta\) are indeed equal to \(\frac{1}{\sin \theta}\) and \(\frac{1}{\cos \theta}\) respectively.

Step 2 :The second step is where the mistake is made. The numerator should be \(\frac{\cos \theta+\sin \theta}{\sin \theta \cos \theta}\), not \(\frac{\cos \theta+\sin \theta}{\sin \theta}\).

Step 3 :So, the first mistake is made in step 2.

Step 4 :Final Answer: \(\boxed{2}\)

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