Answer:

Step-by-step explanation:
Step 1:
Write the expression

Step 2: Expand 

Step 3: Collect similar terms

Step 4: Factor 4 out of the expression to prove that the expression is a multiple of 4.

Answer:
51/2
Step-by-step explanation:
Answer: 9
Step-by-step explanation:
Given
The function is 
To make it a perfect square, compare it with 
Here,

So, c must be square of b i.e. 9

Therefore, value of c is 9.
If the vectors point towards the same direction, the magnitude of the vector quantities are added as in, C = A + B. If they point towards opposite direction, the magnitudes are subtracted giving a resultant vector equal to C = A - B.