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Suatu fungsi dirumuskan dengan . Jika  maka nilai  adalah ....

Pertanyaan

Suatu fungsi dirumuskan dengan begin mathsize 14px style f left parenthesis x right parenthesis equals a x squared plus b x plus c end style. Jika begin mathsize 14px style f left parenthesis 1 right parenthesis equals 6 comma space f apostrophe left parenthesis 0 right parenthesis equals 2 comma space text dan end text space f apostrophe left parenthesis 1 right parenthesis equals 4 end style maka nilai begin mathsize 14px style 2 a plus b plus 3 c end style adalah ....

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Pembahasan Video:

Pembahasan Soal:

Diketahui suatu fungsi begin mathsize 14px style f left parenthesis x right parenthesis equals a x squared plus b x plus c end style.
Nilai begin mathsize 14px style f left parenthesis 1 right parenthesis equals 6 end style, maka

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell f left parenthesis 1 right parenthesis end cell equals 6 row cell a left parenthesis 1 right parenthesis squared plus b left parenthesis 1 right parenthesis plus c end cell equals 6 row cell a plus b plus c end cell equals cell 6 space... left parenthesis 1 right parenthesis end cell row blank blank blank end table end style 

Nilai begin mathsize 14px style f apostrophe left parenthesis 0 right parenthesis equals 2 end style, maka

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell f apostrophe left parenthesis x right parenthesis end cell equals cell 2 a x plus b end cell row cell f apostrophe left parenthesis 0 right parenthesis end cell equals 2 row cell 2 a left parenthesis 0 right parenthesis plus b end cell equals 2 row b equals 2 end table end style 

Nilai begin mathsize 14px style f apostrophe left parenthesis 1 right parenthesis equals 4 end style maka

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell f apostrophe left parenthesis 1 right parenthesis end cell equals 4 row cell 2 a left parenthesis 1 right parenthesis plus b end cell equals 4 row cell 2 a plus b end cell equals cell 4 space... left parenthesis 2 right parenthesis end cell end table end style  

Substitusikan nilai begin mathsize 14px style b equals 2 end style ke persamaan (2) dan didapatkan

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell 2 a plus left parenthesis 2 right parenthesis end cell equals 4 row cell 2 a end cell equals 2 row a equals 1 end table end style 

Substitusikan nilai begin mathsize 14px style a equals 1 end style dan begin mathsize 14px style b equals 2 end style ke persamaan (1), maka didapatkan 

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell a plus b plus c end cell equals 6 row cell 1 plus 2 plus c end cell equals 6 row cell 3 plus c end cell equals 6 row c equals 3 end table end style 

Diperoleh nilai begin mathsize 14px style a equals 1 end stylebegin mathsize 14px style b equals 2 end style, dan begin mathsize 14px style c equals 3 end style, maka nilai begin mathsize 14px style 2 a plus b plus 3 c end style adalah

begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row cell 2 a plus b plus 3 c end cell equals cell 2 left parenthesis 1 right parenthesis plus 2 plus 3 left parenthesis 3 right parenthesis end cell row blank equals cell 2 plus 2 plus 9 end cell row blank equals 13 end table end style 

Pembahasan terverifikasi oleh Roboguru

Terakhir diupdate 12 April 2021

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