Which of the following is incorrect? - Mathematics

प्रश्न

Which of the following is incorrect?

विकल्प

\[\sin x = - \frac{1}{5}\]
cos x = 1
\[\sec x = \frac{1}{2}\]
tan x = 20

MCQ

उत्तर

`bb(sec x = 1/2)`

Explanation:

\[\sin x = - \frac{1}{5}\] is correct as \[- 1 \leq \sin x \leq 1\]

cos x = 1 is correct as cos x = 1 is correct as

\[\sec x = \frac{1}{2}\] is not correct as \[\sec x \in ( - \infty , - 1] \cup [1, \infty )\]

tan x = 20 is correct as tan x can take any real value.

Hence, the correct answer is option \[\sec x = \frac{1}{2}\].

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Trigonometric Equations

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Q 25 Q 24 Q 26

अध्याय 5: Trigonometric Functions - Exercise 5.5 [पृष्ठ ४३]

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आरडी शर्मा Mathematics [English] Class 11

अध्याय 5 Trigonometric Functions
Exercise 5.5 | Q 25 | पृष्ठ ४३

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