Test 8 Section 4 #8

This is a good one to backsolve! Note that you’re asked for a value of x + 1 (as opposed to a value for x) so backsolving is really easy. Start with the easiest ones to try.

    \begin{align*}x+1&=\dfrac{2}{x+1}\\\\\text{C) }\ \ \qquad 2&=\dfrac{2}{2}\\\\2&\ne1\\\\\text{D) }\ \ \qquad 4&=\dfrac{2}{4}\\\\4&\ne 0.5\\\\\text{B) }\qquad\sqrt{2}&=\dfrac{2}{\sqrt{2}}\\\\\sqrt{2}&=\dfrac{2}{\sqrt{2}}\times\dfrac{\sqrt{2}}{\sqrt{2}}\\\\\sqrt{2}&=\dfrac{2\sqrt{2}}{2}\\\\\sqrt{2}&=\sqrt{2}\end{align*}

Choice B looks good to me!

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