How do you prove that $(2sinx)/[secx(cos4x-sin4x)]=tan2x$ ?

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Answer 1 · 2018-05-28T05:32:58

As proved

I suppose the sum is

$(2 sin x) / (sec x (cos^4 x - sin ^4 x)) = tan 2x$

$=> (2 sin x cos x) / ((cos^2 x + sin-^2x)* (cos ^2x - sin^2x))$

$color(crimson)(sin 2x = 2 sin x cos x$ , identity

$color(crimson)(cos^2 x + sin ^2 x -= 1$ , identity

$color(crimson)(cos^2x - sin^2 x = cos 2x$ , identity

$:. => (sin 2x) / (cos 2x) = tan 2x = R H S$

How do you prove that (2sinx)/[secx(cos4x-sin4x)]=tan2x(2sinx)/[secx(cos4x-sin4x)]=tan2x?