26cos(3p/2 - а)=26(cos3p/2*cosa+sin3p/2*sina)=-26sina
sin^2a=1-cos^2a
sin^2a=144/169
sina=12/13
-26*12/13=-24
26cos(3p/2 - а)=26(cos3p/2*cosa+sin3p/2*sina)=-26sina
sin^2a=1-cos^2a
sin^2a=144/169
sina=12/13
-26*12/13=-24