Tse ka Hare
Khatisong ena, re tla hlahloba hore na li-angles tse haufi ke life, re fane ka tlhaloso ea theorem mabapi le tsona (ho kenyeletsoa le liphello tse tsoang ho eona), hape re thathamise litšobotsi tsa trigonometric tsa li-angles tse haufi.
Tlhaloso ea likhutlo tse bapileng
Li-angles tse peli tse bapileng tse etsang mola o otlolohileng ka mahlakore a tsona a ka ntle li bitsoa haufi. Setšoantšong se ka tlase, tsena ke likhutlo α и β.
Haeba likhutlo tse peli li arolelana vertex le lehlakore le le leng, li teng haufi. Tabeng ena, libaka tse ka hare tsa likhutlo tsena ha lia lokela ho kopana.
Molao-motheo oa ho aha sekhutlo se haufi
Re atolosa e 'ngoe ea mahlakoreng a sekhutlo ka vertex ho ea pele, ka lebaka leo ho thehoa sekhutlo se secha, se haufi le sa pele.
Theorem ea angle e haufi
Kakaretso ea likhato tsa li-angles tse haufi ke 180°.
Sekhutlo se haufi 1 + Lehlakore le haufi le 2 = 180 °
Mohlala 1
E 'ngoe ea li-angles tse haufi ke 92°, e 'ngoe ke efe?
Tharollo, ho ea ka theorem e boletsoeng ka holimo, e hlakile:
Lehlakore le haufi 2 = 180 ° - Lehlakore le haufi le 1 = 180 ° - 92 ° = 88 °.
Liphello tse tsoang ho theorem:
- Li-angles tse haufi tsa li-angles tse peli tse lekanang li lekana.
- Haeba angle e haufi le e nepahetseng (90 °), joale e boetse e le 90 °.
- Haeba angle e haufi le e bohale, joale e kholo ho feta 90 °, ke hore ke semumu (le ka tsela e fapaneng).
Mohlala 2
Ha re re re na le angle e bapileng le 75°. E tlameha ho ba kholo ho feta 90°. Ha re e hlahlobeng.
Re sebelisa theorem, re fumana boleng ba angle ea bobeli:
180° – 75° = 105°.
105 ° > 90 °, ka hona angle e boreleli.
Lintho tsa trigonometric tsa li-angles tse haufi
- Li-sine tsa li-angles tse bapileng lia lekana, ke hore, sebe α = sebe β.
- Boleng ba li-cosine le li-tangents tsa li-angles tse haufi lia lekana, empa li na le matšoao a fapaneng (ntle le boleng bo sa hlalosoang).
- cos α = -cos β.
- tg α = -tg β.