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ABC is an isosceles right-angled triangle. Assuming of AB = BC = x, find the value of each of the following trigonometric ratios: sin 45° - Mathematics

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प्रश्न

ABC is an isosceles right-angled triangle. Assuming of AB = BC = x, find the value of each of the following trigonometric ratios: sin 45°

योग

उत्तर

Given that AB = BC = x

∴ AC = `sqrt(AB^2+BC^2) = sqrt(x^2 + x^2) = xsqrt2`

sin 45° = `"AB"/"AC" = x/(xsqrt2) = 1/sqrt2`

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अध्याय 23: Trigonometrical Ratios of Standard Angles [Including Evaluation of an Expression Involving Trigonometric Ratios] - Exercise 23 (A) [पृष्ठ २९१]

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सेलिना Concise Mathematics [English] Class 9 ICSE
अध्याय 23 Trigonometrical Ratios of Standard Angles [Including Evaluation of an Expression Involving Trigonometric Ratios]
Exercise 23 (A) | Q 5.1 | पृष्ठ २९१

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