If \(\tan A=\dfrac{1}{7}\), then what is cos 2A equal to? – McqOptions

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1.	If \(\tan A=\dfrac{1}{7}\), then what is cos 2A equal to?
A.	\(\dfrac{24}{25}\)
B.	\(\dfrac{18}{25}\)
C.	\(\dfrac{12}{25}\)
D.	\(\dfrac{6}{25}\)
Answer» B. \(\dfrac{18}{25}\)

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