Ответы и объяснения

2012-12-13T05:02:38+00:00

sint+cost=0,6 возведем обе части в квадрат

sin^2t+2sintcost+cos^2t=0.36

1+2sintcost=0.36

2sintcost=-0.64

sintcost=-0,32

 

 

 

 tgt sint + ctg t cos t=sint*sint/cost+cost*cost/sint=(sin^3 t+cos^3 t)/sintcost=

={(sint+cost)(sin^2t-sintcost+cos^2t)}/sintcost={(sint+cost)(1-sintcost)}/sintcost=

={0.6*(1+0.32)}/(-0.32)={0.6*1.32}/(-0.32)={0.6*0.33}/(-0.08)=0.3*0.33/(-0.04)=

=-9.9/4=-99/40=-2 19/40