Which describes $f(x) = x^{3} + e^{x}$ ?

Strictly decreasing on

\mathbb{R}

Correct answerYour answerIncreasing on one part of

\mathbb{R}

and decreasing on anotherCorrect answerYour answerStrictly increasing on

\mathbb{R}

Correct answerYour answerConstant on

\mathbb{R}

Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer C

Correct answer: C

$f'(x) = 3 x^{2} + e^{x}$ .
Here $e^{x} > 0$ and $3x^2 \ge 0$ , so $f'(x) > 0$ , so $f$ is strictly increasing on $\mathbb{R}$ .

Worth noting

Adding two increasing functions gives an increasing function.

Ten questions from Increasing & Decreasing Functions, at your own pace.

Ten questions from Increasing & Decreasing Functions, at your own pace.

Which describes f(x)=x3+exf(x) = x^{3} + e^{x}f(x)=x3+ex?