Answer:
-84
Step-by-step explanation:
The formula for the nth term of a geometric progression is
Un = ar^n- 1
The sum of the first six terms of a geometric series (U6) = 21/16
Common ratio = -1/2 ,
a = First term ??
21/16 = a × (-1/2 )^6- 1
21/16 = a ×(-2^-1)^5
21/16 = a × -2^-6
Cross Multiply
16 × a × -2^-6 = 21
a = 21/16 × -2^-6
a = 21/16 ×- 1/2⁶
a = 21/16 × -1/64
a = 21 ÷(-1/4)
a = 21 × -4
a = -84
The first term = 84
Seria 25/5 por que si lo divides seria 5X5=25 ok a ver si te sirve
Answer:
The answer is 21
Step-by-step explanation:
All you have to do is 9+12
Brainliest??
Answer:
A) A(t) = 4500*π - 1600*t
B) A(4) = 7730 in³
C) t = 8,8 sec
Step-by-step explanation:
The volume of the sphere is:
d max = 30 r max = 15 in
V(s) = (4/3)*π*r³ V(s) = (4/3)*π* (15)³
V(s) = 4500*π
A) Amount of air needed to fill the ball A(t)
A(t) = Total max. volume of the sphere - rate of flux of air * time
A(t) = 4500*π - 1600*t in³
B) After 4 minutes
A(4) = 4500*π - 6400
A(4) = 14130 - 6400
A(4) = 7730 in³
C) A(t) = 4500*π - 1600*t
when A(t) = 0 the ball got its maximum volume then:
4500*π - 1600*t = 0
t = 14130/1600
t = 8,8 sec
