Find the quadratic equations whose roots are the reciprocals of the ro...
Explanation:
The quadratic equation whose roots are reciprocal of 2x2 + 5x + 3 = 0 can be obtained by replacing x by 1/x.
Hence, 2(1/x)2 + 5(1/x) + 3 = 0
=> 3x2 + 5x + 2 = 0
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Find the quadratic equations whose roots are the reciprocals of the ro...
Finding Quadratic Equations with Reciprocal Roots
To find the quadratic equations whose roots are the reciprocals of the roots of 2x^2 + 5x + 3 = 0, we can use the following steps:
Step 1: Find the roots of the given quadratic equation.
We can use the quadratic formula to find the roots of 2x^2 + 5x + 3 = 0.
x = (-b ± √(b^2 - 4ac)) / 2a
where a = 2, b = 5, and c = 3.
x = (-5 ± √(5^2 - 4×2×3)) / 2×2
x = (-5 ± √1) / 4
x1 = -3/2
x2 = -1
Step 2: Find the reciprocals of the roots.
The reciprocals of -3/2 and -1 are -2/3 and -1, respectively.
Step 3: Write the quadratic equation with the reciprocals of the roots.
If the roots of a quadratic equation are p and q, then the quadratic equation can be written as:
(x - p)(x - q) = 0
Expanding this equation, we get:
x^2 - (p + q)x + pq = 0
If the roots of the quadratic equation are the reciprocals of p and q, then we can write:
(x - 1/p)(x - 1/q) = 0
Expanding this equation, we get:
x^2 - (1/p + 1/q)x + 1/pq = 0
Since the reciprocals of the roots of 2x^2 + 5x + 3 = 0 are -2/3 and -1, we can substitute these values into the equation above to get:
x^2 - (-3/2 - 1)x + (-2/3)(-1) = 0
Simplifying this equation, we get:
x^2 - (1/2)x - 2/3 = 0
Therefore, the quadratic equation whose roots are the reciprocals of the roots of 2x^2 + 5x + 3 = 0 is 3x^2 + 5x + 2 = 0, which is option (b).