It is C because Since <span><span>{{g(x)}={x^3+2}}<span><span>g(x)</span>=<span><span>x<span><span>3</span><span></span></span></span>+2</span></span></span>g, left parenthesis, x, right parenthesis, equals, x, start superscript, 3, end superscript, plus, 2</span>, we can substitute <span><span>{x^3+2}<span><span>x<span><span>3</span><span></span></span></span>+2</span></span>x, start superscript, 3, end superscript, plus, 2</span> in for <span><span>{g(x)}<span>g(x)</span></span>g, left parenthesis, x, right parenthesis</span>.<span>\begin{aligned}{f(g(x))}&=3(g(x))-1 \\\\ &=3({x^3+2})-1 \\\\ &=3x^3+6-1\\\\ &=3x^3+5 \end{aligned}<span><span><span><span>f(g(x))</span></span><span></span></span><span><span><span>=3(g(x))−1</span></span><span><span>=3(<span><span>x<span><span>3</span><span></span></span></span>+2</span>)−1</span></span><span><span>=3<span>x<span><span>3</span><span></span></span></span>+6−1</span></span><span><span>=3<span>x<span><span>3</span><span></span></span></span>+5</span></span><span></span></span></span></span>
