What is the given probability to determine the smoking and lung cancer are related

What basic trigonometric identity would you use to verify that sin x cos x tan x =1-cos^(2)x?

If f(x)=3x+1 and f^-1=x-1/3, then f^-1(7)=

Which equation represents the model shown? a)1/3 divide 1/6 = 2 b)2/3 divide 1/6 = 2/18 c)1/3 divide 1/6 = 1/18 d)2/3 divide 1/6 =4