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The real number k for which the equation 2x^3 3x k=0 has two distinct real root in [0,1] lies between?
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The real number k for which the equation 2x^3 3x k=0 has two distinct ...
The given equation is 2x^3 + 3x + k = 0. We need to find the range of values for the real number k such that the equation has two distinct real roots in the interval [0,1].

Discriminant:
To determine the nature of the roots of a cubic equation, we can look at its discriminant. For a cubic equation ax^3 + bx^2 + cx + d = 0, the discriminant is given by D = 18abcd - 4b^3d + b^2c^2 - 4ac^3 - 27a^2d^2.

Case 1: Discriminant is positive:
If the discriminant is positive, then the equation has three distinct real roots. Since we are looking for an equation with two distinct real roots, this case is not applicable.

Case 2: Discriminant is zero:
If the discriminant is zero, then the equation has a multiple root. Since we are looking for two distinct real roots, this case is also not applicable.

Case 3: Discriminant is negative:
If the discriminant is negative, then the equation has one real root and two complex conjugate roots. Since we are looking for two distinct real roots, this case is not applicable either.

Therefore, we can conclude that for the equation 2x^3 + 3x + k = 0 to have two distinct real roots in the interval [0,1], the discriminant must be zero.

Calculating Discriminant:
Substituting the given equation 2x^3 + 3x + k = 0 into the general formula for the discriminant, we get:
D = 18(2)(3)(k) - 4(3)^3(k) + (3)^2(0) - 4(2)(0)^3 - 27(2)(k)^2
Simplifying further, we have:
D = 108k - 108k^2

Setting Discriminant to Zero:
Since we want to find the range of values for k, such that the equation has two distinct real roots in the interval [0,1], we set the discriminant D to zero and solve for k:
108k - 108k^2 = 0
Dividing both sides by 108, we get:
k - k^2 = 0
Factoring out k, we have:
k(1 - k) = 0

Range of k:
The equation k(1 - k) = 0 has two roots, k = 0 and k = 1. We need to find the range of values for k in the interval [0,1].

Conclusion:
Therefore, the real number k for which the equation 2x^3 + 3x + k = 0 has two distinct real roots in the interval [0,1] lies between 0 and 1, inclusive.
Community Answer
The real number k for which the equation 2x^3 3x k=0 has two distinct ...
Introduction:
We are given the equation 2x^3 + 3x + k = 0 and we need to find the value of k for which the equation has two distinct real roots in the interval [0, 1].

Analysis:
To find the value of k, we need to consider the nature of the equation and its roots. Let's analyze the equation step by step.

Step 1: Determining the nature of the equation:
The given equation is a cubic equation of the form ax^3 + bx^2 + cx + d = 0, where a = 2, b = 0, c = 3, and d = k.

Step 2: Applying the Intermediate Value Theorem:
To determine the number of real roots in the interval [0, 1], we can apply the Intermediate Value Theorem. According to the theorem, if a continuous function changes sign over an interval, then it must have at least one root in that interval.

Step 3: Checking the sign changes:
Let's substitute the endpoints of the interval [0, 1] into the equation and check for sign changes.

For x = 0:
2(0)^3 + 3(0) + k = k
For x = 1:
2(1)^3 + 3(1) + k = 2 + 3 + k = 5 + k

If k > 0, then the equation changes sign from negative to positive, indicating that there is at least one root in the interval [0, 1].

Step 4: Determining the value of k:
To find the value of k for which the equation has two distinct real roots in the interval [0, 1], we need to consider the case where the equation changes sign twice. This implies that there will be two roots in the interval [0, 1].

Since the equation changes sign only once from negative to positive, we can conclude that there is only one root in the interval [0, 1] for any value of k.

Conclusion:
Based on our analysis, we can conclude that there is no value of k for which the equation 2x^3 + 3x + k = 0 has two distinct real roots in the interval [0, 1].
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The real number k for which the equation 2x^3 3x k=0 has two distinct real root in [0,1] lies between?
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