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2 years ago

If a1= 7 and r=3, find a4

Mathematics

1 answer:

9966 [12]2 years ago

7 0

Answer:

a4 = 189

Step-by-step explanation:

Geometric sequence:

In a geometric sequence, the quotient r between consecutive terms is always the same.

The nth term of the sequence is given by:

$a_n = a_1*r^{n-1}$

In which $a_1$ is the first term.

In this question:

$a_1 = 7, r = 3$

The fourth term is:

$a_4 = 7*3^3 = 189$

a4 = 189

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Given :

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To Find :

Find equations of the spheres with center (1, −1, 6) that touch the following planes.a) xy-plane b) yz-plane c) xz-plane .

Solution :

Distance of the point from xy-plane is :

d = 6 units .

So , equation of circle with center C and radius 6 units is :

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Distance of point from yz-plane is :

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So , equation of circle with center C and radius 1 units is :

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Distance of point from xz-plane is :

d = 1 unit .

So , equation of circle with center C and radius 1 units is :

$(x-1)^2+(x+1)^2+(z-6)^2=1^2\\\\(x-1)^2+(x+1)^2+(z-6)^2=1$

Hence , this is the required solution .

4 0

2 years ago

I’m plz help fast thanks 16

nataly862011 [7]

Answer:

1/2 <3/4

Step-by-step explanation:

1/2 vs 3/4

We need a common denominator of 4

1/2*2/2 vs 3/4

2/4 vs 3/4

Since the denominators are the same, we compare the numerators

2 <3 so

2/4 < 3/4

1/2 <3/4

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Lina20 [59]

Answer:

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