<span>Express each ratio in simplest form 18:30
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Answer:
f(x) = f(-x) = x^2 -1 is an <u>even</u> function
Step-by-step explanation:
When f(x) = f(-x), the function is symmetrical about the y-axis. That is the definition of an <em>even</em> function.
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An odd function is symmetrical about the origin: f(x) = -f(-x).