The equation above is true for all x , where a and b are constants. What is the value of

Question

The equation above is true for all x , where a and b are constants. What is the value of ab ?

Accepted Answer

Choice C is correct. If the equation is true for all x , then the expressions on both sides of the equation will be equivalent. Multiplying the polynomials on the left-hand side of the equation gives . On the right-hand side of the equation, the only -term is . Since the expressions on both sides of the equation are equivalent, it follows that , which can be rewritten as . Therefore, , which gives . Choice A is incorrect. If , then the coefficient of on the left-hand side of the equation would be , which doesn&rsquo;t equal the coefficient of , , on the right-hand side. Choice B is incorrect. If , then the coefficient of on the left-hand side of the equation would be , which doesn&rsquo;t equal the coefficient of , , on the right-hand side. Choice D is incorrect. If , then the coefficient of on the left-hand side of the equation would be , which doesn&rsquo;t equal the coefficient of , , on the right-hand side.

Question the-eq