If a1=1. And r=1/5 find a8

Mathematics

1 answer:

Kruka [31]2 years ago

7 0

Answer:

a₈ = $\frac{1}{78125}$

Step-by-step explanation:

The nth term of a geometric sequence is

$a_{n}$ = a₁ $(r)^{n-1}$

Here a₁ = 1 and r = $\frac{1}{5}$ , then

a₈ = 1 × $(\frac{1}{5}) ^{7}$ = 1 × $\frac{1}{78125}$ = $\frac{1}{78125}$

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Back to our expression:
$4*5 y^{9}+5 y^{6}=4*5 y^{3}*y^{6}+5 y^{6}=4 y^{3}*5y ^{6}+ 5y ^{6}*1=5 y^{6} (4y ^{3} +1)$
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Q2. The answer is D. 12xy^2

$12x y^{5}+60 x^{4} y^{2} -24 x^{3} y^{3}=12x y^{5}+5*12 x^{4} y^{2} -2*12 x^{3} y^{3}$
We will use the rule $x^{a}* x^{b} =x^{a+b}$ to factorise the exponents:
$12x y^{5}+5*12 x^{4} y^{2} -2*12 x^{3} y^{3}= \\ =12x*y^{2}*y^{3}+5*12*x* x^{3} *y^{2}-2*12x* x^{2} *y*y^{2}= \\ =12xy^{2}*y^{3}+12xy^{2}*5 x^{3} -12xy^{2}*2 x^{2} y= \\ =12xy^{2}(y^{3}+5 x^{3}-2 x^{2} y)$
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3 years ago

Mr.rodriguez invests half money in land a tenth in stocks and a twentieth in bonds he puts the remaining 35,000 in his savings a

Elena-2011 [213]

Answer: $100,000

Step-by-step explanation:

Land + Stocks + Bonds + Savings = 100%

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