Question

Prove that this relationship is true (Image Attached)

Answer 1

From the picture, we can see that

`\sin\theta=\frac HB\implies\frac{\sin\theta}C=\frac H{BC}`

`\sin\beta=\frac HC\implies\frac{\sin\beta}B=\frac H{BC}`

which means

`\frac{\sin\theta}C=\frac{\sin\beta}B`