Hi is the answer so this makes it okay to do thing when you have it
Answer:
Your friend is incorrect because if you divide 21 by 7 you will get 3 if you add 7 to 3 you get 10 therefore your friend is incorrect.
We are to find the value of

First we evaluate tan(π/4). The value of tan(π/4) is 1.
So,

sin(π/2) = 1
So,

Thus, we can write:

radians.
So, the answer to this question is π/2 radians.
Answer: There are 60 different ways that he can arrange the books.
Step-by-step explanation:
Since we have given that
Number of computer science books = 5
Number of math books = 3
Number of books selected = 4
Atleast Number of computer science = 2
Atleast number of math book = 1
According to question, he wants at least two computer science books and at least one math book, and he wants to keep the computer science books and the math books together.
So, Number of different ways that he can arrange the books is given by

Hence, there are 60 different ways that he can arrange the books.