Video: Kev sib txheeb ntawm ob sab ntawm daim duab peb sab yog dab tsi?
2024 Tus sau: Leah Nyman | [email protected]. Kawg hloov kho: 2023-12-16 01:18
Txoj Cai 2: Sab ntawm Daim duab peb sab -- Daim duab peb sab Theorem tsis sib xws: Cov theorem no hais tias qhov sib npaug ntawm qhov ntev ntawm ib qho 2 sab ntawm daim duab peb sab yuav tsum muaj ntau dua li tus thib peb sab .) Txoj Cai 3: Kev sib raug zoo ntawm kev ntsuas ntawm sab thiab cov ces kaum hauv a daim duab peb sab : Lub sab hauv loj tshaj plaws thiab sab yog opposite txhua lwm yam.
Xav txog qhov no, kev sib raug zoo ntawm cov ces kaum thiab ob sab ntawm daim duab peb sab yog dab tsi?
Kev sib raug zoo ntawm ob sab thiab cov ces kaum . Hauv ib qho daim duab peb sab , loj tshaj plaws sab thiab loj tshaj kaum sab xis yog opposite ib leeg. Hauv ib qho daim duab peb sab , qhov tsawg tshaj plaws sab thiab tsawg tshaj plaws kaum sab xis yog opposite ib leeg. Hauv ib qho daim duab peb sab , qhov nruab nrab qhov loj me sab thiab nruab nrab qhov loj me kaum sab xis yog opposite ib leeg.
Ib yam nkaus, sab twg ntawm daim duab peb sab ntev tshaj? Ob sab ntawm daim duab peb sab sab xis muaj ntau lub npe sib txawv: Sab ntev tshaj plaws, sab xis kaum sab xis , e npe hypotenuse . Hauv daim duab, tus hypotenuse tau sau npe c. Lwm ob sab hu ua ob txhais ceg ntawm daim duab peb sab.
Qhov thib ob, kev sib raug zoo ntawm ob sab ntawm daim duab peb sab yog dab tsi?
Cov kev sib raug zoo ntawm ob sab thiab cov ces kaum ntawm a txoj cai daim duab peb sab yog lub hauv paus rau trigonometry. Cov sab opposite ua txoj cai lub kaum sab xis yog hu ua hypotenuse ( sab c hauv daim duab). Cov sab nyob ib sab ntawm txoj cai lub kaum sab xis yog hu ua ob txhais ceg (lossis catheti, ib leeg: cathetus).
Puas muaj kev sib raug zoo ntawm qhov ntev ntawm ib sab ntawm daim duab peb sab thiab ntsuas ntawm lub kaum sab xis nws?
os ob sab hauv a daim duab peb sab muaj tib yam ntev , tiam rov qab cov ces kaum muaj tib yam ntsuas . Thiab, yog ob cov ces kaum hauv a daim duab peb sab muaj tib yam ntsuas , tiam ob sab muaj tib yam ntev.
Pom zoo:
Dab tsi yog qhov sib piv ntawm sab ntev hauv 30 60 90 Daim Duab Peb Hlis?
1:2 Xav txog qhov no, uas tuaj yeem yog sab ntev ntawm 30 60 90 txoj cai daim duab peb sab? Cov Lus Qhia rau Nco Ntsoov 30 - 60 - 90 Txoj Cai Nco Ntsoov 30 - 60 - 90 daim cov cai yog teeb meem ntawm kev nco qab qhov piv ntawm 1: √3: 2, thiab paub tias qhov luv tshaj sab ntev yog ib txwm ntxeev lub kaum sab xis luv ( 30 °) thiab ntev tshaj plaws sab ntev yog ib txwm ntxeev lub kaum sab xis loj tshaj plaws ( 90 °).
Qhov sib txawv thiab zoo sib xws ntawm daim duab qhia chaw thiab duab yog dab tsi?
Qhov sib txawv loj ntawm daim duab thaij duab daim duab qhia chaw yog tias daim duab qhia chaw sawv ntsug "phiaj xwm" ntawm ib cheeb tsam, thaum daim duab nthuav tawm cov duab tiag tiag. Cov duab zoo tib yam uas hnav khaub ncaws peb tau yees nrog lub koob yees duab uas nyob hauv txoj hauj lwm kab rov tav
Dab tsi yog kev sib raug zoo ntawm qhov ntev tshaj plaws ntawm ib daim duab peb sab thiab ntsuas ntawm lub kaum sab xis nws?
Sab ntev tshaj plaws hauv daim duab peb sab yog lub kaum sab xis loj tshaj plaws, thiab sab luv tshaj plaws yog lub kaum sab xis me tshaj plaws
Daim duab peb sab txhais li cas ntawm daim duab qhia chaw?
Ib lub cim feem ntau kos kom zoo li nws sawv cev. Piv txwv li, daim duab peb sab yog feem ntau siv los qhia lub roob. Cov suab puam feem ntau pom los ntawm pab pawg ntawm cov dots uas yuav zoo li me ntsis zoo li xuab zeb. Lub hav zoov tuaj yeem muaj cov duab me me uas zoo li ntoo
Koj tuaj yeem qhia dab tsi txog daim duab peb sab thaum muab peb sab ntev?
Txhawm rau txiav txim siab yog tias 3 sab qhov ntev yog daim duab peb sab, siv daim duab peb sab tsis sib xws theorem, uas hais tias qhov sib npaug ntawm 2 sab ntawm daim duab peb sab yuav tsum ntau dua li sab peb. Yog li ntawd, txhua yam koj yuav tsum ua yog ntxiv ua ke txhua qhov ua ke ntawm 2 sab kom pom tias nws loj dua li sab peb