2 2∂∂∂∂∂∂YXYYXX∂ - 2SINX∂ + SINX∂ - COS2X 2∂ = 0 22UU2UU

3. - BAI TAP CHO 16 UNIT 12 CO DAP AN
BAI TAP CHO 16 UNIT 12 CO DAP AN
3. 2

2

∂yx∂ - 2sinx∂ + sinx∂ - cos

2

x

2

∂ = 0

2

u

2

u