PLATE 'XK 



59. Sinysinfoy 'Sin xsin:^x. 



60. Sinysin4y=-3in xsin^x. 



61. Siny3in^y-Sinxsin:^x 



62. Sinysin^y -sin X sinlj X. 



PundersoTiA CnsanilTewH&vwv.Ct 



