Pertanyaan

x → ∞ lim 9 x 2 + 12 x − 3 x + 5 =

$x \to \infty lim 9 x^{2} + 12 x - 3 x + 5 =$

N. Mustikowati

Master Teacher

Mahasiswa/Alumni Universitas Negeri Jakarta

Jawaban terverifikasi

Pembahasan

Dengan menggunakan rumus cepat

$begin mathsize 14px style limit as straight x rightwards arrow infinity of square root of ax squared plus bx plus straight c end root minus square root of px squared plus qx plus straight r end root straight a equals straight p rightwards double arrow fraction numerator straight b minus straight q over denominator 2 square root of straight a end fraction end style$

$begin mathsize 14px style table attributes columnalign right center left columnspacing 0px end attributes row blank blank cell limit as x rightwards arrow infinity of square root of 9 x squared plus 12 x end root minus square root of 9 x squared minus 30 x plus 25 end root end cell row blank equals cell fraction numerator b minus q over denominator 2 square root of a end fraction end cell row blank equals cell fraction numerator 12 minus open parentheses negative 30 close parentheses over denominator 2 square root of 9 end fraction end cell row blank equals cell fraction numerator 12 plus 30 over denominator 2 times open parentheses 3 close parentheses end fraction end cell row blank equals cell 42 over 6 end cell row blank equals 7 end table end style$