prove cos(x)+sin(x)=1

Solution

prove

cos (x) + sin (x) = 1

False

Solution steps

cos (x) + sin (x) = 1

Show that the two sides are not equal

For

cos (x) + sin (x) = 1

plug in

x = 1

cos (1) + sin (1) = 1.38177 \dots

cos (1) + sin (1)

Refine to a decimal form

= 1.38177 \dots

The two sides are not equal

\Rightarrow False

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

sin^{2} (u) (cot^{2} (u) + 1) = 1

\frac{1 + csc ( x )}{cos ( x ) + cot ( x )} = sec (x)

cos (x + \frac{π}{6}) = - sin (x - \frac{π}{3})

4 \cdot cos (2 \cdot x) = 1 - 3 \cdot cos (x)