Answer
Step-by-step explanation:
Replace all occurrences of
+
−
with a single
−
. A plus sign followed by a minus sign has the same mathematical meaning as a single minus sign because
1
⋅
−
1
=
−
1
−
20
−
2
m
Answer:
Step-by-step explanation:
The formula for the dot product of vectors is
u·v = |u||v|cosθ
where |u| and |v| are the magnitudes (lengths) of the vectors. The formula for that is the same as Pythagorean's Theorem.
which is
which is
I am assuming by looking at the above that you can determine where the numbers under the square root signs came from. It's pretty apparent.
We also need the angle, which of course has its own formula.
where uv has ITS own formula:
uv = (14 * 3) + (9 * 6) which is taking the numbers in the i positions in the first set of parenthesis and adding their product to the product of the numbers in the j positions.
uv = 96.
To get the denominator, multiply the lengths of the vectors together. Then take the inverse cosine of the whole mess:
which returns an angle measure of 30.7. Plugging that all into the dot product formula:
gives you a dot product of 96
Answer:
x -2y -2=0
Step-by-step explanation:
using the formula, m= ( Y2 - Y1)/( X2-X1)
the gradient is found. the coordinates chosen are (2,0) and ( 0,-1)
the equation of the line is obtained using the formula
y -y1= m(x -x1)
I could be wrong, but I think it could be D, 18.5.
Just do 5 1/5 divided by 1 2/5