Dot product is
a*b = |a|*|b|*cosα.
In our case
u*u =|u|*|u|*cos 0
u*u =|u|*|u|
12=|u|²
|u|=√12=√(4*3)=2√3
Answer: <span>D. 2√3</span>
<h3>
It is equivalent to 2a+2b</h3>
We use the distributive property.
Multiply the outer term 2 by each term inside ('a' and b)
2 times a = 2a
2 times b = 2b
We add those results to get 2a+2b. We cannot combine these terms as they are not like terms.
Answer is <span>16y + 7z
</span><span><span><span><span>9y</span>+<span>11z</span></span>+<span>7y</span></span>−<span>4z
</span></span><span>=<span><span><span><span><span>9y</span>+<span>11z</span></span>+<span>7y</span></span>+</span>−<span>4z
</span></span></span>Combine Like Terms:
<span>=<span><span><span><span>9y</span>+<span>11z</span></span>+<span>7y</span></span>+<span>−<span>4z
</span></span></span></span><span>=<span><span>(<span><span>9y</span>+<span>7y</span></span>)</span>+<span>(<span><span>11z</span>+<span>−<span>4z</span></span></span>)
</span></span></span><span>=<span><span>16y</span>+<span>7z</span></span></span><span>
</span>