i think it’s perpendicular
Answer: Choice A. sin(A) = cos(B)
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Explanation:
The rule is that sin(A) = cos(B) if and only if A+B = 90.
Note how
- sin(A) = opposite/hypotenuse = BC/AB
- cos(B) = adjacent/hypotenuse = BC/AB
Since both result in the same fraction BC/AB, this helps us see why sin(A) = cos(B). Similarly, we can find that cos(A) = sin(B).
In the diagram below, the angles A and B are complementary, meaning they add to 90 degrees. So this trick only applies to right triangles.
The side lengths can be anything you want, as long as you're dealing with a right triangle.
This can help you
a) since it is discrete we need to think about the sum thing
it it was continuous we would look at an integral thing
so I think if I remember correctly we need to find c such that
<span><span>∑<span>i=0</span>3</span>c(<span>x2</span>+4)=1
b) </span>
problem b is a similar setup
Answer:
18
Step-by-step explanation:
Given
x - 1 = 2 ( add 1 to both sides )
x = 3
Then
2x² = 2(3)² = 2 × 9 = 18