Penjumlahan dan Perkalian Akar-Akar Persamaan Kuadrat

23 Februari 11

Hem, kali ini saya begitu jenuh dengan banyak sekali tugas kantor yang belum terselesaikan. Di sela-sela kesibukan ini saya mencoba untuk berbagi apa yang ada di dalam otak saya saat ini. Materi ini sering keluar dalam ujian akhir nasional tingkat SMA, yaitu mencari hasil penjumlahan atau perkalian atau pembagian akar-akar sebuah persamaan kuadrat. Dalam materi ini kadang kala bervariasi dengan mencari konstanta dari persamaan kuadrat tersebut.
Bentuk baku dari persamaan kuadrat adalah [pmath]ax^2+bx+c=0[/pmath]. Sedangkan contoh soal yang sesuai dengan judul di atas adalah sebagai berikut:
Jika [pmath] alpha dan beta [/pmath] adalah akar-akar persamaan kuadrat [pmath]x^2-8x+12=0[/pmath], maka nilai dari [pmath]alpha+beta [/pmath] adalah….
Untuk menyelesaikn soal tersebut ada dua cara :

Cara I : Mencari akar-akar persamaannya lalu menjumlahkan

[pmath]doubleleftright x^2-8x+12=0[/pmath]
[pmath]doubleleftright (x-2)(x-6)=0[/pmath]
[pmath]doubleleftright x-2=0 atau x-6=0[/pmath]
[pmath]doubleleftright x=2 atau x=6[/pmath]
Jadi , [pmath]alpha = 2 dan beta=6[/pmath], maka [pmath]alpha+beta=2+6=8[/pmath]

Cara II: dengan rumus langsung

Dari persamaan kuadrat [pmath]x^2-8x+12=0[/pmath] diketahui a=1, b=-8 dan c=12.
Maka: [pmath]alpha+beta=-(b/a)=-(-8/1)=8[/pmath], nah sama bukan dengan jawaban cara I.
Sedangkan rumus untuk mecari perkalian dua buah akarnya adalah [pmath]c/a[/pmath]. Itu aja dulu deh, lain kali akan saya sambung dengan variasi soal yang lain.

63 Balasan untuk “Penjumlahan dan Perkalian Akar-Akar Persamaan Kuadrat”

  1. You can not only play but you can also become the developer
    of games of this type and also you can create your
    own apps which will be of same popularity as angry bird and all other games.
    activated: Pressing the screen or (on computer) clicking the mouse
    when the bird has been slung. I am acquiring my whole house carried out section by section as I can afford it.

  2. Clash Of Clan Game mengatakan:

    length;++d)var b=a[d];w(b,”pagespeed_lazy_src”)&&u(b);s[m].
    Two fighters who Farhood doesn’t have to go online to get
    a first look at are Floyd Mayweather Jr. But she can say without
    equivocation that Manny is a cheating criminal.

  3. Bach Ma Temple was built in the ninth century to worship Long Do
    (Dragon. The next line of mice to look at is the Expert line.
    Battlefield Bad Company 2 developed by EA Digital Illusions CE, provides the ultimate modern warfare
    experience.

  4. You ought to be a part of a contest for one of the most useful websites on the internet.
    I’m going to highly recommend this blog!

  5. Freelance Jobs mengatakan:

    Make sure your resume can outshine the competition and that
    you are applying for a work at home job for which you are qualified.
    As it progresses this service will adapt
    and improve but one thing is for sure, it is here to
    stay. The good news is that these home-based careers can be secured
    with the skillset provided by short vocational training courses.

  6. Genuinely when someone doesn’t understand then its up to
    other visitors that they will help, so here it occurs.

  7. attorney utah mengatakan:

    Greetings! Very helpful advice in this particular post! It’s
    the little changes which will make the biggest changes.
    Thanks for sharing!

  8. First off if you are looking for fun ways to use the pool tables down at
    the bar this isn’t going to help. Phoenix (muscle car) is a car you use in a race mission (San Fierro Hills).
    If you are planning to have a website that offers visitors games to
    play, then in order to provide them with the best games you want
    to ensure that you have the best software for games script.

  9. In the 14 turns of gameplay, there are a number of actions which
    can be done to grow your farm. For shoppers looking for the new Xbox
    One, find an exclusive Xbox One holiday bundle with three free games and
    free shipping is available while supplies last. DIRECTV’s Spend Per View UFC
    delivers the passion of environment class kings of the
    cage like Georges St-Pierre, Chuck Liddell, Randy Couture
    and several much more.

Tinggalkan Balasan