Answer: a) 
Step-by-step explanation:
Since we have given that
Number of red marbles = 3
Number of yellow marbles = 4
Number of green marbles = 6
Total number of marbles = 3 +4 +6 = 13
a) the marble is red?
Probability of getting a red marble = 
b) the marble is not yellow?
Probability of not getting yellow = 
c) the marble is either red or green?
Probability of getting either red or green = P(red) + P(green) =
d) the marble is neither red nor green?
Probability of getting neither red nor green = P(getting yellow) = 
Hence, a) 
Answer:
See below
Step-by-step explanation:
Here we need to prove that ,

Imagine a right angled triangle with one of its acute angle as
.
- The side opposite to this angle will be perpendicular .
- Also we know that ,


And by Pythagoras theorem ,

Where the symbols have their usual meaning.
Now , taking LHS ,

- Substituting the respective values,





Since LHS = RHS ,
Hence Proved !
I hope this helps.
Answer:

Step-by-step explanation:
:)