मराठी

If tan A = 1 2 , tan B = 1 3 and tan ( A + B ) = tan A + tan B 1 − tan A tan B , find A + B. - Mathematics

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प्रश्न

If tan `"A" = (1)/(2), tan "B" = (1)/(3) and tan("A" + "B") = (tan"A" + tan"B")/(1 - tan"A" tan"B")`, find A + B.

बेरीज

उत्तर

Since tan `"A" = (1)/(2), tan "B" = (1)/(3)`

tan(A + B) = `(tan"A" + tan"B")/(1 - tan"A" tan"B")`

⇒ tan(A + B) = `(1/2 + 1/3)/(1 - (1/2 xx 1/3))`

⇒ tan(A + B) = `(5/6)/(1 - 1/6)`

⇒ tan(A + B) = `(5/6)/(5/6)`

⇒ tan(A + B) = 1
⇒ tan(A + B) = tan45°
⇒ A + B = 45°.

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पाठ 27: Trigonometrical Ratios of Standard Angles - Exercise 27.1

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फ्रँक Mathematics [English] Class 9 ICSE
पाठ 27 Trigonometrical Ratios of Standard Angles
Exercise 27.1 | Q 27

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