WHY sin x AND cosec x ARE POSITIVE IN SECOND QUADRANT?

जब भी मै बच्चो से पूछता हूँ कि sin x and cosec x, IInd quadrant में positive क्यों होता है? cos x and sec x, IVth में और tan x and cot x IIIrd में? हमेशा answer आता हैं, Sir, ALL SCHOOL TO COLLEGE OR ADD SUGAR TO COFFEE, etc. कुछ ही बच्चों को इसका सही reason पता होता है .

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Let’s see the exact reason.

1. Ist Quadrant

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2. IInd Quadrant

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3. IIIrd Quadrant

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4. IVth Quadrant

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Therefore,

  • All trigonometric ratios are positive in first quadrant.
  • sin and cosec are positive in second quadrant.
  • tan and cot are positive in third quadrant.
  • cos and sec are positive in fourth quadrant.

Post Author: E-Maths