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iousWhere are the zeros for f(x) = 1/2cos 2x - 1 on the interval [0, 2π]?A. noneOB. x =OC. I = 0, π, 2πOD. z = 0,,,3, 2πReset Selection3TNext

iousWhere are the zeros for f(x) = 1/2cos 2x - 1 on the interval [0, 2π]?A. noneOB-example-1
User MADHAIYAN M
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1 Answer

21 votes
21 votes

Given: A function


f(x)=(1)/(2)\cos2x-1

Required: Zeroes of the function in the interval [0,2π]

Step-by-step explanation:

For zero of the function f(x)


\begin{gathered} f(x)=0 \\ (1)/(2)\cos2x-1=0 \end{gathered}

Now,


\begin{gathered} (1)/(2)\cos2x=1 \\ \cos2x=2 \end{gathered}

Now, cos function alsways lies between [-1,1].

It is not equal to 2 in the interval [0,2π].

Hence, the zeroes does not exist in this interval.

Final Answer: The correct answer is option 1.

User Ravenwater
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