1. **State the problem:** We want to find a factor of the polynomial $$60x^4 + 56x^2 + 12$$ of the form $$ax^2 + b$$ where $$a$$ and $$b$$ are positive constants. Then, we need to find a possible value of the product $$ab$$.
2. **Rewrite the polynomial:** Notice that the polynomial is in terms of $$x^4$$ and $$x^2$$. Let $$y = x^2$$, then the polynomial becomes:
$$60y^2 + 56y + 12$$
3. **Factor the quadratic in $$y$$:** We look for factors of the form $$(ay + b)(cy + d)$$ such that:
$$ac = 60, \quad bd = 12, \quad ad + bc = 56$$
4. **Find factor pairs:**
- Factors of 60: (1,60), (2,30), (3,20), (4,15), (5,12), (6,10)
- Factors of 12: (1,12), (2,6), (3,4)
5. **Try pairs to satisfy middle term 56:**
Try $$(a,c) = (6,10)$$ and $$(b,d) = (2,6)$$:
$$ad + bc = 6 \times 6 + 10 \times 2 = 36 + 20 = 56$$ which matches.
6. **So the factorization is:**
$$60y^2 + 56y + 12 = (6y + 2)(10y + 6)$$
7. **Rewrite back in terms of $$x$$:**
$$(6x^2 + 2)(10x^2 + 6)$$
8. **Check the factors:** Both factors are of the form $$ax^2 + b$$ with positive $$a$$ and $$b$$.
9. **Calculate possible values of $$ab$$:**
- For $$6x^2 + 2$$, $$a=6$$ and $$b=2$$, so $$ab = 12$$
- For $$10x^2 + 6$$, $$a=10$$ and $$b=6$$, so $$ab = 60$$
10. **Check the options:** The possible values of $$ab$$ from the factors are 12 and 60, but these are not in the options.
11. **Simplify factors by dividing by common factors:**
$$6x^2 + 2 = 2(3x^2 + 1)$$ and $$10x^2 + 6 = 2(5x^2 + 3)$$
12. **Try the factors $$3x^2 + 1$$ and $$5x^2 + 3$$:**
- $$ab$$ for $$3x^2 + 1$$ is $$3 \times 1 = 3$$
- $$ab$$ for $$5x^2 + 3$$ is $$5 \times 3 = 15$$
13. **Check if $$3x^2 + 1$$ and $$5x^2 + 3$$ are factors:**
Multiply:
$$ (3x^2 + 1)(5x^2 + 3) = 15x^4 + 9x^2 + 5x^2 + 3 = 15x^4 + 14x^2 + 3 $$
14. **Compare with original polynomial:**
Original is $$60x^4 + 56x^2 + 12$$, which is 4 times the above:
$$4(15x^4 + 14x^2 + 3) = 60x^4 + 56x^2 + 12$$
15. **Therefore, the factor $$4(3x^2 + 1)(5x^2 + 3)$$ equals the original polynomial. So the factors $$3x^2 + 1$$ and $$5x^2 + 3$$ are factors of the polynomial up to a constant multiple. Since the problem asks for a factor of the form $$ax^2 + b$$ with positive constants, $$5x^2 + 3$$ is a valid factor.
16. **Hence, a possible value of $$ab$$ is:**
$$5 \times 3 = 15$$
**Final answer:** 15
Factor Polynomial 587311
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