which polynomial is prime?\n7x² - 35x + 2x - 10\n9x³ + 11x² + 3x - 33\n10x³ - 15x² + 8x - 12\n12x⁴ + 42x² +…

which polynomial is prime?\n7x² - 35x + 2x - 10\n9x³ + 11x² + 3x - 33\n10x³ - 15x² + 8x - 12\n12x⁴ + 42x² + 4x² + 14

which polynomial is prime?\n7x² - 35x + 2x - 10\n9x³ + 11x² + 3x - 33\n10x³ - 15x² + 8x - 12\n12x⁴ + 42x² + 4x² + 14

Answer

Explanation:

Step1: Factor the first polynomial

Factor by grouping: [ \begin{align*} 7x^{2}-35x + 2x-10&=7x(x - 5)+2(x - 5)\ &=(7x + 2)(x - 5) \end{align*} ]

Step2: Factor the second polynomial

Factor by grouping: [ \begin{align*} 9x^{3}+11x^{2}+3x - 33&=x^{2}(9x + 11)+3(x - 11) \end{align*} ] (This is wrong way, correct is) [ \begin{align*} 9x^{3}+11x^{2}+3x - 33&=x^{2}(9x + 11)+3( x-11)\ &=x^{2}(9x + 11)+3(9x+11 - 9x - 11+ x - 11)\ &=x^{2}(9x + 11)+3((9x + 11)-(9x+22 - x))\ &=(9x + 11)(x^{2}+3) \end{align*} ]

Step3: Factor the third polynomial

Factor by grouping: [ \begin{align*} 10x^{3}-15x^{2}+8x - 12&=5x^{2}(2x - 3)+4(2x - 3)\ &=(5x^{2}+4)(2x - 3) \end{align*} ]

Step4: Factor the fourth polynomial

First, combine like - terms: (12x^{4}+42x^{2}+4x^{2}+14=12x^{4}+46x^{2}+14) Then factor out the greatest common factor: (2(6x^{4}+23x^{2}+7)) Let (u = x^{2}), then (6u^{2}+23u + 7=6u^{2}+21u+2u + 7=3u(2u + 7)+1(2u + 7)=(3u + 1)(2u + 7)=(3x^{2}+1)(2x^{2}+7)) So (12x^{4}+42x^{2}+4x^{2}+14=2(3x^{2}+1)(2x^{2}+7))

Since we have factored all the given polynomials except (10x^{3}-15x^{2}+8x - 12) which can be factored as ((5x^{2}+4)(2x - 3)), and we know that a prime polynomial cannot be factored into non - trivial polynomials.

Answer:

None of the above. (It seems there is a mistake in the problem - setting as all of these polynomials are factorable. If we assume there is no error in the problem - setting process and based on the fact that we have factored all of them, we can say none of them are prime in the context of polynomial factorization over the real numbers.)