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Can someone help me solve 25x^4-15x^2+2=0? Thank you!?

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Can someone help me solve 25x^4-15x^2+2=0? Thank you!?

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  1. use the quadratic formula. x= (-b+_ sqrt b^2 + 4ac)/2a

    b= -15

    a=25

    c=2


  2. 25 x^4-5 x^2-10 x^2+2=0

    or 5x^2(5x^2-1)-2(5x^2-1)=0

    or (5x^2-2)(5x^2-1)=0

    or 5x^2=2 or 5x^2=1

    or x^2=2/5 or x^2=1/5

    or x=+-sq rt(2/5) or x=+-sq rt(1/5) ANS

  3. 25x^4-15x^2+2=0

    Quadratic Equation: Ax + By + C = 0

    25x^4-15x^2+2=0

    Ax + By + C = 0

    Now look and see that your letters match up with certain numbers....it will always be like this!

    A = 25, B = -15, C = 2

    Now insert these into the Quadratic Formula

    x = -b ± the square root of b^2 - 4ac all divided by 2a

    x = -(-15) ± the square root of (-15)^2 - 4(25)(2) / 2(25)

    x = 15 ± the square root of 125 - 200 / 50

    x = 15 ± the square root of -75 / 50

    x = 15 ± 5i times the square root of 3 / 50

    x = 15 / 50 ±  5i√3 /50

    x = 3 / 10 ±  5i√3 /50

    Your answer is: x = 3 / 10 ±  5i√3 / 50

    Hope this was helpful

  4. believe it or not, you can use the quadratic equation to solve this

    set u=x^2, then your equation becomes:

    25u^2-15u +2=0

    this factors to

    (5u-1)(5u-2)=0

    or u=1/5 and u=2/5

    but u=x^2, so we have that

    x=+/-sqrt[1/5] and x=+/-sqrt[2/5

    so these are the four roots of your original equation

  5. divide everything by 25:

    x^4 - (3/5)x^2 + 2/25 = 0

    factors of 2/25 include (-2/5) and (-1/5), and these add to give -(3/5)

    so the eqn then is,

    (x^2 - 2/5)(x^2- 1/5)

    slns are when

    x^2 = 0.4

    and when,

    x^2 = 0.2

    therefore the slns are four slns which are (-sqt(0.4)), (sqrt(0.4)), (-sqrt(0.2), and sqrt(0.2)  

  6. =(5x^2 -2)(5x^2 -1) =0

    5x^2 =2, 5x^2 =1

    x^2 =2/5, x^2 =1/5

    x=+/- (sqrt 10)/5, +/- (sqrt 5) /5

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