Tính tích phân \(\int_0^{\frac{\pi }{2}} {\sqrt {{{\sin }^7}x{{\cos }^5}x} } dx\)

\(\frac{{5\pi }}{{128\sqrt 2 }}\)

\(\frac{{3\pi }}{{256\sqrt 2 }}\)

\(\frac{\pi }{{256\sqrt 2 }}\)

\(\frac{{7\pi }}{{256\sqrt 2 }}\)