One polynomial that cannot be factored further is x^2 + 2. This is a quadratic polynomial in which the coefficient of x^2 is 1, and the constant term is 2. To check if this polynomial can be factored further, we can use the quadratic formula:
x = (-b ± sqrt(b^2 - 4ac)) / 2a
where a, b, and c are the coefficients of the quadratic polynomial (ax^2 + bx + c). In this case, a = 1, b = 0, and c = 2. Substituting these values into the formula, we get:
x = (-0 ± sqrt(0^2 - 4(1)(2))) / 2(1)
x = ±sqrt(-8)/2
Since the square root of a negative number is not a real number, we can conclude that x^2 + 2 cannot be factored further using real numbers. This is because the solutions to the quadratic equation are imaginary.
As for factoring techniques that might work with this polynomial, we can try factoring by grouping or factoring using the difference of squares formula. However, both of these techniques do not work for this polynomial since it cannot be expressed as the product of two or more quantities that divide it exactly.
In conclusion, x^2 + 2 is a polynomial that cannot be factored further using real numbers, and this is because the solutions to the quadratic equation are imaginary. Factoring by grouping and factoring using the difference of squares formula do not work for this polynomial since it cannot be expressed as the product of two or more quantities that divide it exactly.