25√3cos(x+3π/2) = (1/5)2sin(x+π)
25√3cos(x+(3π/2)) = (1/5)2sin(x+π) (52) √3cos(x+(3π/2)) = (5–1)2sin(x+π) (5) 2√3cos(x+(3π/2)) = 5–2sin(x+π) 2√3cos(x+(3π/2)) = –2sin(x+π) По формулам приведения: cos(x+(3π/2)) =sinx sin(x+π)=–sinx 2√3·sinx=2sinx 2·(√3–1)·sinx=0 sinx=0 x=πk, k∈Z О т в е т. πk, k∈Z