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3 years ago

9

Given rule an= 2(n 2 + 2n), find the first term in the sequence

1 answer:

harkovskaia [24]3 years ago

3 0

$a_n=2(n^2+2n)\\\\a_1-first\ term\to n=1\\\\a_n=2(1^2+2\cdot1)=2(1+2)=2(3)=6\\\\Answer:\ \boxed{B.\ 6}$

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Please solve (21 points)

Ivan

Answer:

he width of the ravin is 47

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2 years ago

Find the angel of FPV

GaryK [48]

Answer:

I can not give an exact answer seeing that I do not have access to that assignment but here is what I have. :)

Step-by-step explanation:

Seeing that the angle between "V" and "R" is a 90 degree angle, I can use that to determine the answer for the angle of F,P,V. It is too high for a 45 degree angle and too short for an 80. I then noticed that R,P,Q is about a 40 degree and since there is a 90 degree angle at V,P,R, I can use that and say F,P,V is about a 60-75 degree angle. Hope this helped! :D

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3 years ago

Evaluate each expression using order of operations <br><br>40-32÷8+5×-2

klio [65]

Answer:

26

Step-by-step explanation:

40-32÷8+5×-2

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40-4+-10

36+-10

26

6 0

3 years ago

Can you solve this?

marusya05 [52]

Answer:

D

Step-by-step explanation:

The area (A) of a trapezoid is calculated as

A = 0.5h(a + b)

where h is the perpendicular height and a, b the parallel sides.

Given A = 120, then

0.5 × 8(a + b) = 120, that is

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4 years ago

The second term of a GP is 4, the fifth term is 81. Find the seventh term

navik [9.2K]

Answer:

The seventh term of a G.P is

$t_{7} = 33,097.211$

Step-by-step explanation:

<u><em>step(i):</em></u><em>-</em>

<em>Given the second term of a G.P is '4'</em>

<em>The general term of nth term is </em>

<em></em> $t_{n} = ar^{n-1}$ <em></em>

<em></em> $t_{4} = ar^{4-1} =4$

$ar^{3} =4$ …(i)

<em>Also Given the fifth term of a G.P is '81'</em>

$t_{5} = ar^{5-1} =81$

$ar^{4} =81$ …(ii)

<u><em>Step(ii)</em></u>:-

<em>Dividing the equation (ii) divided by (i)</em>

<em /> $\frac{ar^{4} }{ar^{3} } = \frac{81}{4}$ <em />

<em>cancellation ' a' and 'r' terms , we get</em>

<em /> $r = \frac{81}{4}=20.25$ <em />

<em>substituting 'r' Value in equation (i), we get</em>

<em></em> $ar^{3} =4$ <em></em>

$a(\frac{81}{4}) ^{3} =4$

$a = \frac{4X4X4X4}{(81)^{3} }= \frac{256}{531,441}$

a = 0.00048

<u><em>Step(iii):-</em></u>

<u><em>The seventh term of G.P </em></u>

<em>The general term of nth term is </em>

<em></em> $t_{n} = ar^{n-1}$ <em></em>

<em></em> $t_{7} = (0.00048)(20.25)^{7-1}$ <em></em>

<em></em> $t_{7} = (0.00048)(20.25)^{6}= 33,097.211$ <em></em>

<em></em>

<em></em>

3 0

4 years ago