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

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

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

prove

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

False

Solution steps

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

Show that the two sides are not equal

For

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

plug in

x = 0

\frac{sin ( 0 )}{- cos ( 0 )} = 0

\frac{sin ( 0 )}{- cos ( 0 )}

Use the following trivial identity:

sin (0) = 0

sin (0)

sin (x)

periodicity table with

2 πn

cycle:

x 0 \frac{π}{6} \frac{π}{4} \frac{π}{3} \frac{π}{2} \frac{2 π}{3} \frac{3 π}{4} \frac{5 π}{6} sin (x) 0 \frac{1}{2} \frac{2}{2} \frac{3}{2} 1 \frac{3}{2} \frac{2}{2} \frac{1}{2} x π \frac{7 π}{6} \frac{5 π}{4} \frac{4 π}{3} \frac{3 π}{2} \frac{5 π}{3} \frac{7 π}{4} \frac{11 π}{6} sin (x) 0 - \frac{1}{2} - \frac{2}{2} - \frac{3}{2} - 1 - \frac{3}{2} - \frac{2}{2} - \frac{1}{2}

= 0

Use the following trivial identity:

cos (0) = 1

cos (0)

cos (x)

periodicity table with

2 πn

cycle:

x 0 \frac{π}{6} \frac{π}{4} \frac{π}{3} \frac{π}{2} \frac{2 π}{3} \frac{3 π}{4} \frac{5 π}{6} cos (x) 1 \frac{3}{2} \frac{2}{2} \frac{1}{2} 0 - \frac{1}{2} - \frac{2}{2} - \frac{3}{2} x π \frac{7 π}{6} \frac{5 π}{4} \frac{4 π}{3} \frac{3 π}{2} \frac{5 π}{3} \frac{7 π}{4} \frac{11 π}{6} cos (x) - 1 - \frac{3}{2} - \frac{2}{2} - \frac{1}{2} 0 \frac{1}{2} \frac{2}{2} \frac{3}{2}

= 1

= \frac{0}{- 1}

Simplify

= 0

The two sides are not equal

\Rightarrow False

sin (θ) \cdot tan (θ) \cdot cos (θ) = sin^{2} (θ)

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

\frac{1}{1 - sin ( x )} = - csc (x)

cos^{2} (x) - cos^{2} (x) = cot^{2} (x) cos^{2} (x)

2 cos (2 (\frac{π}{4})) = 16 cos (2 (\frac{π}{4}))