मराठी

If A lies in the second quadrant and 3tanA + 4 = 0, then the value of 2cotA – 5cosA + sinA is equal to ______. - Mathematics

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प्रश्न

If A lies in the second quadrant and 3tanA + 4 = 0, then the value of 2cotA – 5cosA + sinA is equal to ______.

पर्याय

  • `(-53)/10`

  • `23/10`

  • `37/10`

  • `7/10`

MCQ
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उत्तर

If A lies in the second quadrant and 3tanA + 4 = 0, then the value of 2cotA – 5cosA + sinA is equal to `23/10`.

Explanation:

Given that: 3tanA + 4 = 0

A lies in the second quadrant


tanA = `(-4)/3`

cosA = `(-3)/5`   .......[A lies in second quadrant]

And sinA = `4/5` and cotA = `(-3)/4`

∴ 2cotA – 5cosA + sinA = `2((-3)/4) -5((-3)/5) + 4/5`

= `(-3)/2 + 3 + 4/5`

= `(-15 + 30 + 8)/10`

= `23/10`

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Values of Trigonometric Functions at Multiples and Submultiples of an Angle
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पाठ 3: Trigonometric Functions - Exercise [पृष्ठ ५८]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 11
पाठ 3 Trigonometric Functions
Exercise | Q 55 | पृष्ठ ५८

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