34/(cos101+cos191)=34/[cos²(90+11)+cos²(180+11)]=
=34/(sin²11+cos²11)=34/1=34
4sin17cos17/cos56=2sin34/cos(90-34)=2sin34/sin34=2
22/(cos²34+cos²124)=22/[cos²(90-56)+cos²(180-56)]=
=22/(sin²56+cos²56)=22/1=22
sina=2√29/29,a∈(0;π/2)
cosa=√(1-sin²a)=√(1-4/29)=√(25/29)=5/√29=5√29/29
tga=sina/cosa=2√29/29:5√29/29=2√29/29*29/5√29=2/5=0,4