STEP - BY - STEP EXPLANATION
What to find?
The angle between the given vectors.
Given:
u = 5i – 2j and v = 2i + 3j.
To solve the given problem, we will follow the steps below:
Step 1
Write the formula that can be use to solve the above.
[tex]cos\theta=\frac{\vec{a}\vec{.b}}{\vec{|a}\vec{||b}|}[/tex]Step 2
Determine;
→ →
a. b
[tex]\begin{gathered} \vec{a}\vec{.b}=(5)(2)+(-2)(3) \\ \\ =10-6 \\ \\ =4 \end{gathered}[/tex]Step 3
Determine;
→ →
|a| and | b|
[tex]\begin{gathered} \vec{|a|}=\sqrt{5^2+(-2)^2} \\ \\ =\sqrt{25+4} \end{gathered}[/tex][tex]=\sqrt{29}[/tex][tex]\begin{gathered} \vec{|b|}=\sqrt{2^2+3^2} \\ \\ =\sqrt{4+9} \\ \\ =\sqrt{13} \end{gathered}[/tex]Step 4
Substitute the values into the formula.
[tex]\begin{gathered} cos\theta=\frac{4}{\sqrt{29}\times\sqrt{13}} \\ \\ =\frac{4}{\sqrt{377}} \end{gathered}[/tex]Step 5
Take the arc cos of both-side.
[tex]\theta=cos^{-1}(0.20601)[/tex][tex]\theta=78.1\degree[/tex]ANSWER
θ = 78. 1°