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If f(x) = | cos x |, then πf(3π4) is ______.

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Question

If f(x) = | cos x |, then `f((3π)/4)` is ______.

Options

  • 1

  • – 1

  • `(-1)/sqrt(2)`

  • `1/sqrt(2)`

MCQ
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Solution

If f(x) = | cos x |, then `f((3π)/4)` is `underlinebb(1/sqrt(2))`.

Explanation:

f(x) = | cos x |

`\implies f((3π)/4) = |cos  (3π)/4|`

= `|cos(π - π/4)|`

= `|- cos  π/4|`

= `|-1/sqrt(2)|`

= `1/sqrt(2)`

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2022-2023 (March) Delhi Set 3

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