Answer:
What do You mean?
Step-by-step explanation:
What kind of subject is this?
Answer:
x² - 20 = 0
Using the quadratic formula

a = 1 b = 0 c = -20
So we have

Hope this helps you.
Answer:
Radius of the convergence is R = 
and,
The Interval of convergence is 
Step-by-step explanation:
Given function : Σ(21x)^k
Now,
Using the ratio test, we have
R = 
or
R = 
or
R = 
now,
for convergence R|x| < 1
Therefore,
< 1
or

and,
Radius of the convergence is R = 
and,
The Interval of convergence is 
Let the boy be B and the girl be G
there are six possible outcomes
BGG, GBB, GBG, BGB, BBB, and GGG
therefore the probability of getting one boy and two girls is

also the probability of getting 3 girls is
Hello :
f(x) = 4(x2 − 6x + 3² - 3²____) + 20 = 4((x2 − 6x + 3²) - 3²____) + 20<span>
= 4(x-3)² -36+20
</span>f(x) = 4(x-3)² -16 (vertex form)