Question

The following reasons might explain why the equation for the length just obtained using components is the same as the answer obtained using geometry (Equation 1 above); 1. $c$ and $\theta$ are supplementary angles, that is, $\theta + c = \pi$. 2. The cosine function satisfies $cos(\alpha) = -cos(\pi - \alpha)$. 3. Cosine is an even function of its argument, so the extra negative sign in one expression does not matter. Which of these reasons is/are necessary to show that $\sqrt{A^2 + B^2 - 2AB \cos(c)} = \sqrt{A^2 + B^2 + 2AB \cos(\theta)}$? 1 only 2 only 3 only 1 and 2 

          The following reasons might explain why the equation for the length just obtained using components is the same as the answer obtained using geometry (Equation 1 above);
1. $c$ and $\theta$ are supplementary angles, that is, $\theta + c = \pi$.
2. The cosine function satisfies $cos(\alpha) = -cos(\pi - \alpha)$.
3. Cosine is an even function of its argument, so the extra negative sign in one expression does not matter.
Which of these reasons is/are necessary to show that
$\sqrt{A^2 + B^2 - 2AB \cos(c)} = \sqrt{A^2 + B^2 + 2AB \cos(\theta)}$?
1 only
2 only
3 only
1 and 2
Show more…
The following reasons might explain why the equation for the length just obtained using components is the same as the answer obtained using geometry (Equation 1 above); 1. c and θ are supplementary angles, that is, θ + c = π. 2. The cosine function satisfies cos(α) = -cos(π - α). 3. Cosine is an even function of its argument, so the extra negative sign in one expression does not matter. Which of these reasons is/are necessary to show that √(A^2 + B^2 - 2AB cos(c)) = √(A^2 + B^2 + 2AB cos(θ))? 1 only 2 only 3 only 1 and 2

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The following reasons might explain why the equation for the length just obtained using components is the same as the answer obtained using geometry (Equation 1 above). c and θ are supplementary angles, that is, θ + c = π. The cosine function satisfies cos(α) = -cos(π - α). Cosine is an even function of its argument, so the extra negative sign in one expression does not matter. Which of these reasons is/are necessary to show that √(A^2 + B^2 - 2ABcos(c)) = √(A^2 + B^2 + 2ABcos(θ))? 1 only 2 only 3 only 1 and 2 ASUS Vivobook r O1and2 O3only O 2 only O 1only not matter. 2 Which of these reasons is/are necessary to show that The cosine function satisfies cos = -cos same as the answer obtained using geometry (Equation 1 above): 3. Cosine is an even function of its argument so the extra negative sign in one expression does 1/28/2024 5:27 PM
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Transcript

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00:01 In the right triangle, we know that cosine of 180 minus a will be equal to u divide by v.
00:08 From here we get u is equal to minus b cosine of a because cosine of 1 .80 minus theta will be equal to minus cos theta...
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