To determine the possible values of the constant p for which the expression px² + 12x + 4p + px is a perfect square, we can rewrite the expression as:
px² + px + 12x + 4p
Grouping the terms:
p(x² + x) + 12(x + p)
Factoring out x² + x:
p(x(x + 1)) + 12(x + p)
To make this expression a perfect square, we need to complete the square for both terms.
For p(x(x + 1)), we need to add the square of half the coefficient of the x term, which is (1/2)^2 = 1/4. However, we also need to consider the factor of p in front, so we actually need to add p(1/4):
p(x(x + 1) + 1/4).
For 12(x + p), we need to add the square of half the coefficient of the x term, which is (12/2)^2 = 36. However, we also need to consider the factor of p in front, so we actually need to add p(36):
12(x + p) + p(36).
Combining these terms:
p(x(x + 1) + 1/4) + 12(x + p) + p(36).
To make this expression a perfect square, we need to set these two terms equal to each other:
x(x + 1) + 1/4 = 12.
Expanding and rearranging:
x² + x + 1/4 - 12 = 0.
x² + x - 47/4 = 0.
To solve this quadratic equation, we can use the quadratic formula:
x = (-b ± √(b² - 4ac)) / (2a).
In this case, a = 1, b = 1, and c = -47/4. Plugging in these values:
x = (-(1) ± √((1)² - 4(1)(-47/4))) / (2(1)).
Simplifying:
x = (-1 ± √(1 + 47/4)) / 2.
x = (-1 ± √(51/4)) / 2.
x = (-1 ± √51/2) / 2.
Since p is a constant, it can be any real number. Therefore, there are no specific values for p that would make the expression a perfect square.
Find possible values of the constant p if the expression px²+12x+4p+px is a perfect square
3 answers
px^2+12x+4p+px = px^2 + (p+12)x + 4p = p(x^2 + (1 + 12/p)x + 4)
We need p to be a perfect square, and it is clear by inspection that if p=4, we have
4(x^2 + 4x + 4) = (2(x+2))^2
We need p to be a perfect square, and it is clear by inspection that if p=4, we have
4(x^2 + 4x + 4) = (2(x+2))^2
Apologies for the previous incorrect response. You are correct that we can rewrite the expression as px² + (p+12)x + 4p.
To make this expression a perfect square, we need the coefficient of x to be twice the square root of the constant term. In this case, the constant term is 4p.
Therefore, (p+12) = 2√(4p)
Simplifying the equation:
p + 12 = 2√(4p)
p + 12 = 4√p
(√p)^2 - 4√p + 12 = 0
Letting z = √p, we can rewrite the equation as:
z^2 - 4z + 12 = 0
Applying the quadratic formula:
z = (4 ± √(4² - 4(1)(12)))/2
z = (4 ± √(16 - 48))/2
z = (4 ± √(-32))/2
Since we can't take the square root of a negative number, there are no possible values of p that make the expression a perfect square.
To make this expression a perfect square, we need the coefficient of x to be twice the square root of the constant term. In this case, the constant term is 4p.
Therefore, (p+12) = 2√(4p)
Simplifying the equation:
p + 12 = 2√(4p)
p + 12 = 4√p
(√p)^2 - 4√p + 12 = 0
Letting z = √p, we can rewrite the equation as:
z^2 - 4z + 12 = 0
Applying the quadratic formula:
z = (4 ± √(4² - 4(1)(12)))/2
z = (4 ± √(16 - 48))/2
z = (4 ± √(-32))/2
Since we can't take the square root of a negative number, there are no possible values of p that make the expression a perfect square.