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IgorLugansk [536]

2 years ago

9

Find the 5th term of the GP is 48 and it 8th term is 384. find the first term and the common

1 answer:

rewona [7]2 years ago

7 0

Answer:

$\text{1st term} = 3\\\\\text{Common ratio} = 2$

Step by step explanation:

$\text{Given that,}\\\\\text{5th term} = ar^{5-1} = ar^4 = 48~~~~~~~~...(i)\\ \\\text{8th term} = ar^{8-1} = ar^7 = 384~~~~~~~...(ii)\\\\\text{1st term,}~ a = ?\\\\\text{Common ratio,}~ r = ?\\\\(ii) \div (i):\\\\~~~~~~\dfrac{ar^7}{ar^4}=\dfrac{384}{48}\\\\\implies r^{7-4} = 8\\\\\implies r^3 = 8\\\\\implies r^3 = 2^3\\\\\implies r =2\\\\\text{Substitute r = 2 in eq (i):}\\\\~~~~~~a\cdot 2^4 = 48\\\\\implies 16a =48\\\\\implies a = \dfrac{48}{16}\\\\\implies a = 3\\$

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sashaice [31]

Don’t now the answer sorry

3 0

3 years ago

I need help I don’t understand this

Hatshy [7]

Answer:

Step-by-step explanation:

lets say "a" for the empty line,

for small triangle; y^2 = 2^2 + x^2

right triangle; we say a for empty line, a^2= 6^2 + x^2

and big triangle covering both triangles, 8^2 = y^2 + a^2

lets add left sides and right sides in each;

x^2 + 4 + x^2 + 36 + y^2 + a^2 = y^2 + a^2 + 64 and we can delete same things for both sides

y^2 and a^2 can be deleted and 4+36 - 64

2(x^2)=24

x^2= 12

and x will be √12

so, y^2 = x^2 + 2^2 which means y^2 = 12+4 y=16

4 0

3 years ago

<img src="https://tex.z-dn.net/?f=%20%5Cfrac%7Bx%20%7B%7D%5E%7B2%7D%20-%204%20%7D%7B%20%5Csqrt%7Bx%20%7B%7D%5E%7B2%7D%20-%206x%2

Nimfa-mama [501]

First of all, we can observe that

$x^2-6x+9 = (x-3)^2$

So the expression becomes

$\dfrac{x^2-4}{\sqrt{(x-3)^2}} = \dfrac{x^2-4}{|x-3|}$

This means that the expression is defined for every $x\neq 3$

Now, since the denominator is always positive (when it exists), the fraction can only be positive if the denominator is also positive: we must ask

$x^2-4 \geq 0 \iff x\leq -2 \lor x\geq 2$

Since we can't accept 3 as an answer, the actual solution set is

$(-\infty,-2] \cup [2,3) \cup (3,\infty)$

7 0

3 years ago

if a tree 20 meters tall casts a shadow 30 meters long, what is the angle of elevation from the shadow to the tip of the tree, t

inn [45]

sketch the situation

a trigonometric function that is a relation between the angle of elevation and the 2 sides of the rectangles is the tan

$\tan \theta=\frac{opp}{adj}$ $\tan \theta=\frac{20}{30}=\frac{2}{3}$

find the inverse

$\begin{gathered} \tan ^{-1}(\frac{2}{3})=\theta \\ \theta=33.69º \end{gathered}$

after rounding the angle of elevation is 34º.

6 0

1 year ago

mojhsa [17]

Answer:

A. Subtraction

B. Subtraction

C. x+4=11

-4 -4

D. x=7

Step-by-step explanation:

3 0

3 years ago