Is sin(2x)=(2sin(x))/(sec(x)) ?

The answer to whether sin(2x)=(2sin(x))/(sec(x)) is True

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prove sin(2x)=(2sin(x))/(sec(x))

prove

sin (2 x) = \frac{2 sin ( x )}{sec ( x )}

True

Solution steps

sin (2 x) = \frac{2 sin ( x )}{sec ( x )}

Manipulating right side

\frac{2 sin ( x )}{sec ( x )}

Express with sin, cos

\frac{2 sin ( x )}{sec ( x )}

Use the basic trigonometric identity:

sec (x) = \frac{1}{cos ( x )}

= \frac{2 sin ( x )}{\frac{1}{c o s ( x )}}

Simplify

\frac{2 sin ( x )}{\frac{1}{c o s ( x )}} : 2 sin (x) cos (x)

\frac{2 sin ( x )}{\frac{1}{c o s ( x )}}

Apply the fraction rule:

\frac{a}{\frac{b}{c}} = \frac{a \cdot c}{b}

= \frac{2 sin ( x ) cos ( x )}{1}

Apply rule

\frac{a}{1} = a

= 2 sin (x) cos (x)

= 2 sin (x) cos (x)

= 2 cos (x) sin (x)

Rewrite using trig identities

2 cos (x) sin (x)

Use the Double Angle identity:

2 sin (x) cos (x) = sin (2 x)

= sin (2 x)

= sin (2 x)

We showed that the two sides could take the same form

\Rightarrow True

4 sin^{2} (x) tan (x) = tan (x)

sin (x) = \frac{3}{4} \cdot \frac{sin ( x )}{\frac{3}{4}}

(tan (x) + 2) = 2 + sec (x) sin (x)

tan (θ - 4 5^{\circ}) + tan (θ + 4 5^{\circ}) = 2 tan (2 θ)

tan (2 θ) - tan (θ) = tan (θ) sec (2 θ)

Is sin(2x)=(2sin(x))/(sec(x)) ?
The answer to whether sin(2x)=(2sin(x))/(sec(x)) is True