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3 years ago

Given |u| = 10 at ∠135° and |v| = 5 at ∠30°, what expression can be used to find |u + v|?

Mathematics

2 answers:

mihalych1998 [28]3 years ago

8 0

Answer:

(10)2 + (5)2 – 2(10)(5) cos(75°)

This is the answer edge 2020

astraxan [27]3 years ago

5 0

Answer:

B, $10^{2} + 5^{2}- 2(10)(5)cos(75)$

Step-by-step explanation:

Using the law of cosines, which is $c^{2}=a^{2}+b^{2}-2ab cos(C)$ , you can simply insert all the values.

c=|u+v|

a= r value of u (10)

b= r value of v (5)

To find C, you simply have to subtract v from u, and then subtract that number from 180 to find the reference angle.

I.E.: ∠135 - ∠30 = ∠105 ↔ 180 - 105 = 75 = C

so, the completed equation would be 10^{2} + 5^{2}- 2(10)(5)cos(75)

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Answer: $25.9\%$

Step-by-step explanation:

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3 years ago

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zmey [24]

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Step-by-step explanation:

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3 years ago

Read 2 more answers

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Brut [27]

Answer:

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Step-by-step explanation:

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