Question

Find the angle between the following two vectors: <2, -5> and <4, 21>. Round your answer to the nearest degree. You do not need to include the degree symbol in your solution.

Answer 1

To find the angle we have the formula

and we have that

`\begin{gathered} \lvert{a}\rvert=√(4+25)=√(29) \\ \lvert b\rvert=√(16+441)=√(457) \end{gathered}`

so we get that

`\cos\alpha\approx-0.8425867691776014`

Then

`\alpha=147.41429264608558°`

The answer is 147.41429264608558