Question 1: Evaluate the following:

i)      ii)      iii)      iv)     v)  

Answer:

i)      

ii)      

iii)   

iv)    

v)  

Question 2: If , find the value of .

Answer:

Given

Applying the Formula, when

Therefore

Question 3: If , find .

Answer:

Given

Applying the formula, when

Therefore

Question 4: If , find .

Answer:

Given

Applying the formula, when

Therefore

Question 5: If , find .

Answer:

Given

Applying the formula, when

Therefore

Question 6: If , find .

Answer:

Given

Applying the formula, when

Therefore

Question 7: If , find .

Answer:

Given

Applying the formula, when

Therefore

Question 8: If , find .

Answer:

Comparing LHS with RHS we get,

If   and    

If , then

Hence can be or .

Question 9: If , find .

Answer:

Question 10: If , find .

Answer:

Question 11: If , find .

Answer:

Question 12: If  and are in AP, then find .

Answer:

and are in AP

or

Question 13: If , find .

Answer:

Given

Question 14: If , find .

Answer:

Given

Applying the formula, when

Therefore

Question 15: If , then find the value of

Answer:

Given