Show that 2 tan20° + 4 tan40° + 8 tan 80° = 9(cot10° - tan10°).
Thank you :)
Put values
tan 20 = 0.3639, tan 40 = 0.8390, tan 80 = 5.6713, cot 10 = 5.6713, tan 10 =0.1763
(2 x 0.3696) + 4(0.8390) + 8(5.6713) = 49.4656
9( 5.6713 - 0.1763) =49.455
Pretty close :)
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