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Tan(x)+cot(x)=sec(x)csc(x)

User Ewooycom
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The LHS is equal to the RHS, and the trigonometric identity is proved:


\[ \tan(x) + \cot(x) = \sec(x) \csc(x) \]

To prove the trigonometric identity
\( \tan(x) + \cot(x) = \sec(x) \csc(x) \),we'll start with the left-hand side (LHS) and manipulate it to match the right-hand side (RHS).

Starting with the LHS:


\[ \tan(x) + \cot(x) \]

We know that
\( \tan(x) = (\sin(x))/(\cos(x)) \) and
\( \cot(x) = (1)/(\tan(x)) = (\cos(x))/(\sin(x)) \).

Now, substitute these expressions into the LHS:


\[ (\sin(x))/(\cos(x)) + (\cos(x))/(\sin(x)) \]

To combine these fractions, find a common denominator, which is the product of the denominators
(\( \cos(x) * \sin(x) \))


\[ (\sin^2(x) + \cos^2(x))/(\cos(x) \sin(x)) \]

Recall that
\( \sin^2(x) + \cos^2(x) = 1 \) (the Pythagorean identity), so the expression becomes:


\[ (1)/(\cos(x) \sin(x)) \]

Now, express
\( (1)/(\cos(x) \sin(x)) \) in terms of sec(x) and csc(x):


\[ (1)/(\cos(x) \sin(x)) = (1)/(\cos(x)) \cdot (1)/(\sin(x)) = \sec(x) \csc(x) \]

Therefore, we've shown that the LHS is equal to the RHS, and the trigonometric identity is proved:


\[ \tan(x) + \cot(x) = \sec(x) \csc(x) \]

User Jkatzer
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