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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 ratio: cos 45°
उत्तर
Given that AB = BC = x
∴ AC = `sqrt(AB^2+BC^2) = sqrt(x^2 + x^2) = xsqrt2`
cos 45° =`"BC"/"AC" = x/(xsqrt2) = 1/sqrt2`
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