Question

Sin A=5/13
Найти ctg если cos=12/13, tg=5/12

Answer 1

tgα=sinα/cosα=(5/13)/(12/13)=5/12
0∠sinα,0∠cosα, α∈(0,90°)
ctgα=1/tgα=1/(5/12)=12/5
ctgα=12/5