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

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प्रश्न

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

योग

उत्तर

tan(A - B) = `(1)/sqrt(3)`

⇒ tan(A - B) = tan30°
⇒ A - B = 30° ......(i)
tan(A + B) = `sqrt(3)`
⇒ tan(A + B) = tan60°
⇒ A + B = 60° ........(ii)
Adding (i) and (ii)
A - B + A + B = 30° + 60°
⇒ 2A = 90°
⇒ A = 45°
Substituting value of A in (i)
A - B = 30°
45° - B = 30°
B = 15°
Therefore,
A = 45° and B = 15°.

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अध्याय 27: Trigonometrical Ratios of Standard Angles - Exercise 27.1

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फ्रैंक Mathematics [English] Class 9 ICSE
अध्याय 27 Trigonometrical Ratios of Standard Angles
Exercise 27.1 | Q 24

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