IDNLearn.com: Your trusted source for finding accurate answers. Ask anything and receive immediate, well-informed answers from our dedicated community of experts.
Sagot :
Certainly! Let's verify the trigonometric identity [tex]\(\sin (A + B) = \sin A \cos B + \cos A \sin B\)[/tex] using the given angles [tex]\(A = 60^\circ\)[/tex] and [tex]\(B = 30^\circ\)[/tex].
### Step-by-Step Solution:
1. Calculate [tex]\(\sin A\)[/tex] and [tex]\(\cos A\)[/tex]:
- Given [tex]\(A = 60^\circ\)[/tex]:
[tex]\[ \sin A = \sin 60^\circ = \frac{\sqrt{3}}{2} \approx 0.8660254037844386 \][/tex]
[tex]\[ \cos A = \cos 60^\circ = \frac{1}{2} \approx 0.5000000000000001 \][/tex]
2. Calculate [tex]\(\sin B\)[/tex] and [tex]\(\cos B\)[/tex]:
- Given [tex]\(B = 30^\circ\)[/tex]:
[tex]\[ \sin B = \sin 30^\circ = \frac{1}{2} \approx 0.49999999999999994 \][/tex]
[tex]\[ \cos B = \cos 30^\circ = \frac{\sqrt{3}}{2} \approx 0.8660254037844387 \][/tex]
3. Calculate [tex]\(\sin (A + B)\)[/tex]:
- Here, [tex]\(A + B = 60^\circ + 30^\circ = 90^\circ\)[/tex]:
[tex]\[ \sin (A + B) = \sin 90^\circ = 1 \][/tex]
4. Compute the right-hand side of the identity [tex]\(\sin A \cos B + \cos A \sin B\)[/tex]:
[tex]\[ \sin A \cos B + \cos A \sin B = \left( \frac{\sqrt{3}}{2} \right) \left( \frac{\sqrt{3}}{2} \right) + \left( \frac{1}{2} \right) \left( \frac{1}{2} \right) \][/tex]
This simplifies to:
[tex]\[ = \frac{3}{4} + \frac{1}{4} = 1 \][/tex]
5. Compare the left-hand side and the right-hand side:
- The left-hand side [tex]\(\sin (A + B)\)[/tex] is 1.
- The right-hand side [tex]\(\sin A \cos B + \cos A \sin B\)[/tex] is 1.
Since both sides are equal, we have successfully verified the identity:
[tex]\[ \sin (A + B) = \sin A \cos B + \cos A \sin B \][/tex]
Thus, [tex]\(\sin (60^\circ + 30^\circ) = \sin 60^\circ \cos 30^\circ + \cos 60^\circ \sin 30^\circ\)[/tex] holds true.
### Step-by-Step Solution:
1. Calculate [tex]\(\sin A\)[/tex] and [tex]\(\cos A\)[/tex]:
- Given [tex]\(A = 60^\circ\)[/tex]:
[tex]\[ \sin A = \sin 60^\circ = \frac{\sqrt{3}}{2} \approx 0.8660254037844386 \][/tex]
[tex]\[ \cos A = \cos 60^\circ = \frac{1}{2} \approx 0.5000000000000001 \][/tex]
2. Calculate [tex]\(\sin B\)[/tex] and [tex]\(\cos B\)[/tex]:
- Given [tex]\(B = 30^\circ\)[/tex]:
[tex]\[ \sin B = \sin 30^\circ = \frac{1}{2} \approx 0.49999999999999994 \][/tex]
[tex]\[ \cos B = \cos 30^\circ = \frac{\sqrt{3}}{2} \approx 0.8660254037844387 \][/tex]
3. Calculate [tex]\(\sin (A + B)\)[/tex]:
- Here, [tex]\(A + B = 60^\circ + 30^\circ = 90^\circ\)[/tex]:
[tex]\[ \sin (A + B) = \sin 90^\circ = 1 \][/tex]
4. Compute the right-hand side of the identity [tex]\(\sin A \cos B + \cos A \sin B\)[/tex]:
[tex]\[ \sin A \cos B + \cos A \sin B = \left( \frac{\sqrt{3}}{2} \right) \left( \frac{\sqrt{3}}{2} \right) + \left( \frac{1}{2} \right) \left( \frac{1}{2} \right) \][/tex]
This simplifies to:
[tex]\[ = \frac{3}{4} + \frac{1}{4} = 1 \][/tex]
5. Compare the left-hand side and the right-hand side:
- The left-hand side [tex]\(\sin (A + B)\)[/tex] is 1.
- The right-hand side [tex]\(\sin A \cos B + \cos A \sin B\)[/tex] is 1.
Since both sides are equal, we have successfully verified the identity:
[tex]\[ \sin (A + B) = \sin A \cos B + \cos A \sin B \][/tex]
Thus, [tex]\(\sin (60^\circ + 30^\circ) = \sin 60^\circ \cos 30^\circ + \cos 60^\circ \sin 30^\circ\)[/tex] holds true.
We value your presence here. Keep sharing knowledge and helping others find the answers they need. This community is the perfect place to learn together. Find the answers you need at IDNLearn.com. Thanks for stopping by, and come back soon for more valuable insights.