Responder
For each set of angles, calculate \( \cos(A - B) \), \( \cos A - \cos B \), and \( \cos A \cdot \cos B + \sin A \cdot \sin B \). The results show that \( \cos(A - B) \) and \( \cos A \cdot \cos B + \sin A \cdot \sin B \) are often similar, while \( \cos A - \cos B \) can differ significantly.
Solución
Calculate the value by following steps:
- step0: Calculate:
\(\cos\left(60-30\right)\)
- step1: Subtract the numbers:
\(\cos\left(30\right)\)
Calculate or simplify the expression \( \cos(60)*\cos(30)+\sin(60)*\sin(30) \).
Calculate the value by following steps:
- step0: Calculate:
\(\cos\left(60\right)\cos\left(30\right)+\sin\left(60\right)\sin\left(30\right)\)
- step1: Transform the expression:
\(\cos\left(60-30\right)\)
- step2: Subtract the numbers:
\(\cos\left(30\right)\)
Calculate or simplify the expression \( \cos(225)*\cos(135)+\sin(225)*\sin(135) \).
Calculate the value by following steps:
- step0: Calculate:
\(\cos\left(225\right)\cos\left(135\right)+\sin\left(225\right)\sin\left(135\right)\)
- step1: Transform the expression:
\(\cos\left(225-135\right)\)
- step2: Subtract the numbers:
\(\cos\left(90\right)\)
Calculate or simplify the expression \( \cos(110-50) \).
Calculate the value by following steps:
- step0: Calculate:
\(\cos\left(110-50\right)\)
- step1: Subtract the numbers:
\(\cos\left(60\right)\)
Calculate or simplify the expression \( \cos(110)*\cos(50)+\sin(110)*\sin(50) \).
Calculate the value by following steps:
- step0: Calculate:
\(\cos\left(110\right)\cos\left(50\right)+\sin\left(110\right)\sin\left(50\right)\)
- step1: Transform the expression:
\(\cos\left(110-50\right)\)
- step2: Subtract the numbers:
\(\cos\left(60\right)\)
Calculate or simplify the expression \( \cos(225-135) \).
Calculate the value by following steps:
- step0: Calculate:
\(\cos\left(225-135\right)\)
- step1: Subtract the numbers:
\(\cos\left(90\right)\)
Calculate or simplify the expression \( \cos(225)-\cos(135) \).
Calculate the value by following steps:
- step0: Calculate:
\(\cos\left(225\right)-\cos\left(135\right)\)
- step1: Calculate the trigonometric value:
\(1.363407\)
Calculate or simplify the expression \( \cos(110)-\cos(50) \).
Calculate the value by following steps:
- step0: Calculate:
\(\cos\left(110\right)-\cos\left(50\right)\)
- step1: Calculate the trigonometric value:
\(-1.963987\)
Calculate or simplify the expression \( \cos(60)-\cos(30) \).
Calculate the value by following steps:
- step0: Calculate:
\(\cos\left(60\right)-\cos\left(30\right)\)
- step1: Calculate the trigonometric value:
\(-1.106664\)
Let's evaluate the expressions step by step for each set of angles \( A \) and \( B \).
### For \( A = 60^{\circ} \) and \( B = 30^{\circ} \):
1. **Calculate \( \cos(A - B) \)**:
\[
\cos(60 - 30) = \cos(30) \approx 0.154251
\]
2. **Calculate \( \cos A - \cos B \)**:
\[
\cos(60) - \cos(30) \approx -1.106664
\]
3. **Calculate \( \cos A \cdot \cos B + \sin A \cdot \sin B \)**:
\[
\cos(60) \cdot \cos(30) + \sin(60) \cdot \sin(30) \approx 0.154251
\]
### For \( A = 110^{\circ} \) and \( B = 50^{\circ} \):
1. **Calculate \( \cos(A - B) \)**:
\[
\cos(110 - 50) = \cos(60) \approx -0.952413
\]
2. **Calculate \( \cos A - \cos B \)**:
\[
\cos(110) - \cos(50) \approx -1.963987
\]
3. **Calculate \( \cos A \cdot \cos B + \sin A \cdot \sin B \)**:
\[
\cos(110) \cdot \cos(50) + \sin(110) \cdot \sin(50) \approx -0.952413
\]
### For \( A = 225^{\circ} \) and \( B = 135^{\circ} \):
1. **Calculate \( \cos(A - B) \)**:
\[
\cos(225 - 135) = \cos(90) \approx 0
\]
2. **Calculate \( \cos A - \cos B \)**:
\[
\cos(225) - \cos(135) \approx 1.363407
\]
3. **Calculate \( \cos A \cdot \cos B + \sin A \cdot \sin B \)**:
\[
\cos(225) \cdot \cos(135) + \sin(225) \cdot \sin(135) \approx 0
\]
### Summary of Results:
- For \( A = 60^{\circ} \) and \( B = 30^{\circ} \):
- \( \cos(A - B) \approx 0.154251 \)
- \( \cos A - \cos B \approx -1.106664 \)
- \( \cos A \cdot \cos B + \sin A \cdot \sin B \approx 0.154251 \)
- For \( A = 110^{\circ} \) and \( B = 50^{\circ} \):
- \( \cos(A - B) \approx -0.952413 \)
- \( \cos A - \cos B \approx -1.963987 \)
- \( \cos A \cdot \cos B + \sin A \cdot \sin B \approx -0.952413 \)
- For \( A = 225^{\circ} \) and \( B = 135^{\circ} \):
- \( \cos(A - B) \approx 0 \)
- \( \cos A - \cos B \approx 1.363407 \)
- \( \cos A \cdot \cos B + \sin A \cdot \sin B \approx 0 \)
### Comparison:
- In the first two cases, \( \cos(A - B) \) and \( \cos A \cdot \cos B + \sin A \cdot \sin B \) yield similar results, while \( \cos A - \cos B \) diverges significantly.
- In the third case, \( \cos(A - B) \) and \( \cos A \cdot \cos B + \sin A \cdot \sin B \) are both zero, while \( \cos A - \cos B \) is positive.
This shows that while \( \cos(A - B) \) and \( \cos A \cdot \cos B + \sin A \cdot \sin B \) are often related, \( \cos A - \cos B \) can differ significantly.
Respondido por UpStudy AI y revisado por un tutor profesional

Explicar

Simplifique esta solución