Expression frac{{{{tan }^2}20° - {{sin }^2}20° }}{{{{tan }^2}20° ,·,{{sin }^2}20° }

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3.Trigonometrical Ratios, Functions and Identities

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The expression $\frac{{{{\tan }^2}20^\circ - {{\sin }^2}20^\circ }}{{{{\tan }^2}20^\circ \,\cdot\,{{\sin }^2}20^\circ }}$ simplifies to

A

a rational which is not integral

B

a surd

C

a natural which is prime

D

a natural which is not composite

Solution

$tan^220^° – sin^220^° = tan^220^° (1 – cos^220^°) = tan^220^°\, sin^220^°$

Hence $ N^r = D^r$

Standard 11

Mathematics

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