Maths problem A level?

I have x^2 +4x-14=0 and i need to give it in the form of p+q√2

Thanks in advance

Comments

  • Use the quadratic formula:

    x = ( -b ± √(b^2 - 4ac) ) / 2a

    x = ( -4 ± √(16 + 56) ) / 2

    x = ( -4 ± √(72) ) / 2

    x = ( -4 ± 6√(2) ) / 2

    x = -2 ± 3√(2)

    And your two answers are:

    x = -2 + 3√(2)

    x = -2 - 3√(2)

    Which means:

    p = -2

    q = ±3

  • x² +4x – 14 = 0

    x² +4x = 14

    x² +4x + 4 = 14 + 4

    (x + 2)² = 18

    (x + 2) = ± √18

    (x + 2) = ± 3√2

    x = –2 ± 3√2

  • p=-2, q=3

  • x² + 4x - 14 = 0

    x² + 2x = 14 + 2²

    x² + 2x = 14 + 4

    (x + 2)² = 18

    x + 2 = ± √18

    Answer: (x + 2 + √18)(x + 2 - √18) are the factors.

  • #eleven: Multiply the two the numerator and the denominator by potential of the conjugate of the denominator. which potential multiply by potential of the sq. root of 5 minus the squareroot of x. #23: cube the two sides of the equation, which leaves you with: 3x-2=8. clean up from there. #31a: i do no longer remember the thank you to try this. #40: Divide 40 3 by potential of four, and get a the remainder of three. So the anser is comparable to it could be if i is raised to the third ability. If I remember wisely, i^3 is -i. #40 8: i do no longer understand. #40 9: that's (7x6x5x4x3x2x1)/(4x3x2x1). So in certainty that's 7x6x5. #fifty 4: the variety is all actual numbers (so that's for all organic log purposes that are like ln(x-c) whjere c is a few consistent). For the area, you could no longer enable the interior a organic log funtion ever be 0 or under 0. subsequently x is larger than 3 is the area. to locate the x-intercept: ln(x-3) =0. e^(ln(x-3))=e^0. x-3=a million. x=4 is the x-intercept.

  • Recall the quadratic formula for a x^2 + b x + c = 0;

    x = [-b +/- sqrt( b^2 - 4 a c)] / (2 a)

    Here, a = 1, b = 4, and c = -14, so

    x = [-4 +/- sqrt( 16 - 4(1)(-14) )] / 2(1)

    = [-4 +/- sqrt(72)] / 2

    = [-4 +/- sqrt(2*36)] / 2

    = [-4 +/- sqrt(2)*sqrt(36)] / 2

    = [-4 +/- 6*sqrt(2)] / 2

    = -2 +/- 3*sqrt(2)

    So, p = -2 and q = 3.

    I hope that helped.

Sign In or Register to comment.