Last updated at Jan. 28, 2022 by
This question is similar to Ex 4.4, 2 (i) Chapter 4 Class 10 - Quadratic Equations
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Question 1 – Choice 2 Find the values of k for which the quadratic equation 3𝑥2 + 𝑘𝑥 + 3 = 0 has real and equal roots. Given 3𝑥2 + 𝑘𝑥 + 3 = 0 Comparing equation with ax2 + bx + c = 0 Here, a = 3, b = 𝑘, c = 3 Since the equation has 2 equal roots, D = 0 b2 – 4ac = 0 Putting values 𝑘^2−4 × 3 × 3=0 𝑘^2−36=0 𝑘^2=36 𝑘 = ±√36 𝒌 = ±𝟔 Hence, 𝒌 = 𝟔 or 𝒌 = −𝟔
Find the values of k for which the quadratic equation 3 x2+k x+3=0 has real and equal roots?
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I'm a junior in high school. I'm taking Pre-Calculus 11 online and I'm struggling with this question.
I've started using b2 - 4ac, but I don't know where to go from there or if that's even the best way to approach this question.
For what values of k does 3x2- kx + 2 have two equal real roots?
For 3x2 - kx + 2, a=3, b=k, c=2.
I know that for a quadratic equation to have 2 equal roots, b2 - 4ac = 0.
k2 - 4(3)(2) = b2 - 4ac
k2 - 4(3)(2) = 0
k2 -24 = 0
k2 = 24
k =
I don't know how to continue on from there. I would appreciate all the help I can get!
… For what values of k does 3x2- kx + 2 have two equal real roots?
… I know that for a quadratic equation to have 2 equal roots, b2 - 4ac = 0
I don't know how to continue on from there …
Fix the sign issue. Then, do you know how to simplify the radical? (Most instructors would like to see the answers simplified.)
Last edited: Aug 29, 2018
… a=3, b=k, c=2
… k2 - 4(3)(2) = b2 - 4ac
Because -k is squared, in this exercise, you came out okay. Be mindful of coefficient signs. :cool:
I'm a junior in high school. I'm taking Pre-Calculus 11 online and I'm struggling with this question.
I've started using b2 - 4ac, but I don't know where to go from there or if that's even the best way to approach this question.
For what values of k does 3x2- kx + 2 have two equal real roots?
For 3x2 - kx + 2, a=3, b=k, c=2.
I know that for a quadratic equation to have 2 equal roots, b2 - 4ac = 0.
k2 - 4(3)(2) = b2 - 4ac
k2 - 4(3)(2) = 0
k2 -24 = 0
k2 = 24
k =
I don't know how to continue on from there. I would appreciate all the help I can get!
Don't forget that there are two numbers whose square is 24!
Find both, and simplify the radicals. Otherwise, you're doing fine. I'd do just what you did.