Question

вычислите cos(arccos 5/13+arcsin 7/25)

Answer 1

cos(arccos 5/13+arcsin 7/25)=(5/13+√(625/625-49/625))=5/13+24/25=437/325

Answer 2

$cos(arccos5/13+arcsin7/25)=\=cos(arccos5/13)cos(arcsin7/25)-\-sin(arccos5/13)sin(arcsin7/25)=\=5/13sqrt{1-(7/25)^2}-7/15sqrt{1-(5/13)^2}=\=5/13sqrt{576/625}-7/15sqrt{144/169}=\=5/13*24/25 -7/15*12/13=24/65-84/65=-12/13$