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Question
If f(x) = | cos x |, then `f((3π)/4)` is ______.
Options
1
– 1
`(-1)/sqrt(2)`
`1/sqrt(2)`
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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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