The value of cos(x) that supports Steve's claim is 1/√10
Given the following trigonometry identity
tan(x) = 3
According to the theorem;
tan x = opposite/adjacent = 3/1
Opposite = 3
Adjacent = 1
Determine the hypotenuse
hyp = √3² + 1²
hyp = √10
Since cos(x) = adj/hyp
cos(x) = 1/√10
Hence the value of cos(x) that supports Steve's claim is 1/√10
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