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Math Help - roots of equation

  1. #1
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    roots of equation

    if i am asked roots of equation for ax^2+bx+c=0 which formula is this, it may seem easy but i not sure what asking
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    Quote Originally Posted by gregorio View Post
    if i am asked roots of equation for ax^2+bx+c=0 which formula is this, it may seem easy but i not sure what asking
    If a\not = 0 and let \Delta = b^2 - 4ac.

    If \Delta >0 the roots are \frac{-b+\sqrt{\Delta}}{2a},\frac{-b-\sqrt{\Delta}}{2a}

    If \Delta = 0 there is just one root -\frac{b}{2a}

    If \Delta < 0 the roots are \frac{-b+i\sqrt{-\Delta}}{2a}, \frac{-b-i\sqrt{-\Delta}}{2a}. Where i is defined to be so that i^2 = -1.
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    Quote Originally Posted by gregorio View Post
    if i am asked roots of equation for ax^2+bx+c=0 which formula is this, it may seem easy but i not sure what asking
    You should use the quadratic formula for the roots.

    RonL
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    Quote Originally Posted by gregorio View Post
    if i am asked roots of equation for ax^2+bx+c=0 which formula is this, it may seem easy but i not sure what asking
    Or, if you want some practice, you can solve this using the completing the square method. The final answer is the quadratic formula.

    -Dan
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