Is 1/(cos(x))-cos(x)=sin(x)tan(x) ?

The answer to whether 1/(cos(x))-cos(x)=sin(x)tan(x) is True

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prove 1/(cos(x))-cos(x)=sin(x)tan(x)

prove

\frac{1}{cos ( x )} - cos (x) = sin (x) tan (x)

True

Solution steps

\frac{1}{cos ( x )} - cos (x) = sin (x) tan (x)

Manipulating right side

sin (x) tan (x)

Express with sin, cos

sin (x) tan (x)

Use the basic trigonometric identity:

tan (x) = \frac{sin ( x )}{cos ( x )}

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

Simplify

sin (x) \frac{sin ( x )}{cos ( x )} : \frac{sin ^{2} ( x )}{cos ( x )}

sin (x) \frac{sin ( x )}{cos ( x )}

Multiply fractions:

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

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

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

sin (x) sin (x)

Apply exponent rule:

a^{b} \cdot a^{c} = a^{b + c}

sin (x) sin (x) = sin^{1 + 1} (x)

= sin^{1 + 1} (x)

Add the numbers:

1 + 1 = 2

= sin^{2} (x)

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

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

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

Rewrite using trig identities

\frac{sin ^{2} ( x )}{cos ( x )}

Use the Pythagorean identity:

cos^{2} (x) + sin^{2} (x) = 1

sin^{2} (x) = 1 - cos^{2} (x)

= \frac{1 - cos ^{2} ( x )}{cos ( x )}

= \frac{1 - cos ^{2} ( x )}{cos ( x )}

Expand

\frac{1 - cos ^{2} ( x )}{cos ( x )} : \frac{1}{cos ( x )} - cos (x)

\frac{1 - cos ^{2} ( x )}{cos ( x )}

Apply the fraction rule:

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

\frac{1 - cos ^{2} ( x )}{cos ( x )} = \frac{1}{cos ( x )} - \frac{cos ^{2} ( x )}{cos ( x )}

= \frac{1}{cos ( x )} - \frac{cos ^{2} ( x )}{cos ( x )}

Cancel

\frac{cos ^{2} ( x )}{cos ( x )} : cos (x)

\frac{cos ^{2} ( x )}{cos ( x )}

Cancel the common factor:

cos (x)

= cos (x)

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

= - cos (x) + \frac{1}{cos ( x )}

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

We showed that the two sides could take the same form

\Rightarrow True

sec (u) cos (u) - sin^{2} (u) = cos^{2} (u)

1 + cot^{2} (\frac{x}{2}) = \frac{2}{sin ( x ) tan ( \frac{x}{2} )}

\frac{tan ^{2} ( x )}{sec ( x )} + cos (x) = sec (x)

tan^{2} (x) cot^{2} (x) = 1

cos (π + θ) = - cos (θ)

Is 1/(cos(x))-cos(x)=sin(x)tan(x) ?
The answer to whether 1/(cos(x))-cos(x)=sin(x)tan(x) is True