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A toddler is jumping on another pogo stick whose length of their spring can be represented by the function g of theta equals 1 minus sine squared theta plus radical 3 period At what times are the springs from the original pogo stick and the toddler's pogo stick lengths equal?

A toddler is jumping on another pogo stick whose length of their spring can be represented-example-1
User Ognian Gloushkov
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1 Answer

23 votes
23 votes
Answer:

The springs from the original pogo stick and the toddler's pogo stick length are equal after 1 second and 0.9994 second.

Step-by-step explanation:

The given functions are:


\begin{gathered} f(\theta)=2\cos \theta+\sqrt[]{3} \\ g(\theta)=1-\sin ^2\theta+\sqrt[]{3} \end{gathered}

The springs from the original pogo stick and the toddler's pogo stick length are equal when both functions coincide

That is;


\begin{gathered} f(\theta)=g(\theta) \\ \Rightarrow2\cos \theta+\sqrt[]{3}=1-\sin ^2\theta+\sqrt[]{3} \end{gathered}

Solving the equation, we have:


\begin{gathered} 2\cos \theta+\sqrt[]{3}=1-\sin ^2\theta+\sqrt[]{3} \\ Subtract\sqrt[]{3}\text{ from both sides} \\ 2\cos \theta=1-\sin ^2\theta \end{gathered}

Note the identity below:


\begin{gathered} \cos ^2\theta+\sin ^2\theta=1 \\ \cos ^2\theta=1-\sin ^2\theta \end{gathered}

This means


\begin{gathered} 2\cos \theta=\cos ^2\theta \\ \cos ^2\theta-2\cos \theta=0 \\ \cos \theta(\cos \theta-2)=0 \\ \cos \theta=0 \\ \Rightarrow\theta=\cos ^(-1)(0)=1 \\ \\ OR \\ \cos \theta-2=0 \\ \cos \theta=2 \\ \theta=\cos ^(-1)(2)=0.9994 \end{gathered}

The springs from the original pogo stick and the toddler's pogo stick length are equal after 1 second and 0.9994 second.

User Juan Ariza
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