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Show that the equation is not an identity. 1/sin (x)+cos (x) =csc (x) +sec (x)

User Mutp
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Final answer:

The equation 1/sin(x) + cos(x) is not equivalent to csc(x) + sec(x) because cos(x) is not equal to 1/cos(x). This demonstrates that the given equation is not a trigonometric identity.

Step-by-step explanation:

The equation presented is 1/sin(x) + cos(x) ≠ csc(x) + sec(x), where csc(x) is the cosecant function and sec(x) is the secant function. We'll use trigonometric identities to show that this equation is not an identity.

First, we know that csc(x) is the reciprocal of sin(x), and sec(x) is the reciprocal of cos(x), so csc(x) = 1/sin(x) and sec(x) = 1/cos(x). Plugging these into the equation,
we get 1/sin(x) + cos(x) ≠ 1/sin(x) + 1/cos(x).

From this step, it's clear that the equation is not an identity because cos(x) does not equal 1/cos(x). In other words, a function and its reciprocal are not the same unless the original function is 1 or -1, which cos(x) is not for all x.

User Leon Bouquiet
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