Vector function

a fighter aircraft, can fire a laser beam forward, has a trajectory r(t) = <(5-t), (21-t ^ 2), (3- (t ^ 3/27))>. Prove that there is just a moment t in which the pilot can reach a target located at the origin. the answer that I consider doing the calculations is t = 3 or 7.

I Need help!

#Calculus

Easy Math Editor

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Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$