Lub quadratic muaj nuj nqi f(x)=ax2 + bx + c yuav have xwb tus nqi siab tshajthaum tus thawj coefficient los yog lub cim ntawm "a" yog qhov tsis zoo. Thaum "a" tsis zoo, daim duab ntawm lub quadratic muaj nuj nqi yuav yog parabola uas qhib. Tus nqi siab tshaj plaws yog "y" ua haujlwm ntawm lub vertex ntawm parabola.
Puas txhua plaub plaub muaj qhov tsawg kawg nkaus lossis siab tshaj tus nqi?
Nrhiav lub Domain thiab ntau yam ntawm Quadratic Function. Ib tus lej twg tuaj yeem yog tus nqi nkag ntawm qhov kev ua haujlwm quadratic. Yog li ntawd, tus sau ntawm ib qho kev ua haujlwm quadratic yog txhua tus lej tiag. Vim tias parabolas muaj qhov siab tshaj plaws lossis qhov tsawg kawg nkaus ntawm qhov vertex, qhov ntau yog txwv.
Puas tag nrho plaub lub luag haujlwm muaj tus nqi siab tshaj?
Tus nqi siab tshaj plaws ntawm kev ua haujlwm yog qhov chaw uas muaj nuj nqi nce mus txog qhov siab tshaj plaws, lossis vertex, ntawm daim duab. Yog tias koj qhov kev sib npaug quadratic muaj qhov tsis zoo, nws tseem yuav muaj qhov siab tshaj plaws. … Yog hais tias koj muab cov mis y=ax2 + bx + c, ces koj yuav nrhiav tau tus nqi siab tshaj uas siv cov mis max=c - (b2 / 4a)
Puas tag nrho cov kev sib npaug plaub npaug muaj qhov tsawg kawg nkaus?
Nrhiav lub Domain thiab ntau yam ntawm Quadratic Function. Txhua tus lej tuaj yeem yog tus nqi nkag ntawm qhov kev ua haujlwm quadratic. Yog li ntawd, tus sau ntawm ib qho kev ua haujlwm quadratic yog txhua tus lej tiag. Vim tias parabolas muaj qhov siab tshaj plaws lossis qhov tsawg kawg nkaus, qhov ntau raug txwv.
Koj pom qhov tsawg kawg nkaus thiab qhov siab tshaj plaws ntawm kev sib npaug plaub npaug li cas?
Nrhiav max/min: Muaj ob txoj hauv kev los nrhiav qhov siab tshaj plaws / qhov tsawg kawg nkaus rau f(x)=ax2 + bx + c: Muab lub quadratic rau hauv daim ntawv f (x)=a(x − h) 2 + k, thiab qhov siab tshaj plaws / yam tsawg kawg nkaus yog k thiab nws tshwm sim ntawm x=h. Yog hais tias ib tug > 0, ces lub parabola qhib, thiab nws yog ib tug tsawg kawg nkaus functional nqi ntawm f.
