(1) f(sin x) dx = f(cos x) dx

(2) f(sin 2x).sin x dx = f(sin 2x).cos x dx

(3)

(4)

(5) dx = dx =

(6) dx = dx =

(7)

(8) dx = dx =

(9)

(10) dx = dx =

(11) dx =

(12)

(13) dx = dx = dx = (a + b)

(14) log(1 + tan x) dx = log 2

(15) log(sin x) dx = log(cos x) dx = – log 2 = log ()

(16)