Q.

Riya and her sister visited their friend’s farmhouse. Upon arrival, Riya noticed that the roof of her friend’s house was shaped like a trapezium, with the dimensions indicated in the figure.

On the basis of above information, answer the following questions:

 

(iii) (b) Find the value ofsin 2A+sin 2DsinAsecD

1 1  
2 2  
3 5  
4 4  

Ans.

(1)

We have,

sin 2A+sin 2DsinAsecD=sin 230°+sin 260°sin30°sec60°A=30°D=60°=122+32212×2=14+341=11=1