Mathematics, 24.12.2019 00:31 angelmilla

Explain why the x coordinates of the points where the graphs of the equations y=2^-x and y=4^x+3 intersects

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Hello,

y=2^(-x)
y=2^(2x)+3

==>2^(2x)+3=1/2^x
==>2^(3x)+3*2^x-1=0 (1)
Let's assume u=2^x
(1)==>u^3+3*u-1=0

which as 3 roots
u=0.322185354626 or
u = -0.161092677313 + i1.754380959784 or
u = -0.161092677313 - i1.754380959784.

Let's take the real solution

0.322185354626=2^x
==>x=ln(0.322185354626) / ln(2)
x=-1,6340371790199...

an other way is
f(x)=2^(3x)+3*2^x-1
f(-2)=1/64+3/4-1=-15/64 <0
f(-1)=1/8+1-1=1/8>0
==> there is a solution betheen -2<x<-1

Explain why the x coordinates of the points where the graphs of the equations y=2^-x and y=4^x+3 int

Explain why the x coordinates of the points where the graphs of the equations y=2^-x and y=4^x+3 int

Answer from: Quest

$x=\frac{3}{4}$

step-by-step explanation:

we are given

$-6+2x=6x-9$

since, we have to isolate x on anyone side

so, we can move all x terms on one side

subtract both sides by 2x

$-6+2x-2x=6x-9-2x$

$-6=4x-9$

add both sides by 9

$-6+9=4x-9+9$

$3=4x$

divide both sides by 4

we get

$x=\frac{3}{4}$

Answer from: Quest

step-by-step explanation:

i found the life tables for the year 2012.

life table of males at age 30. probability of dying between ages x and x+1

total population:

29–30 . . . . . . . . . . . . 0.001030

30–31 . . . . . . . . . . . . 0.001061

males:

29–30 . . . . . . . . . . . . 0.001420

30–31 . . . . . . . . . . . . 0.001448

white population

29–30 . . . . . . . . . . . . 0.001005

30–31 . . . . . . . . . . . . 0.001037

white males

29–30 . . . . . . . . . . . . 0.001372

30–31 . . . . . . . . . . . . 0.001399

non hispanic white population

29–30 . . . . . . . . . . . . 0.001083

30–31 . . . . . . . . . . . . 0.001116

non hispanic white males

29–30 . . . . . . . . . . . . 0.001477

30–31 . . . . . . . . . . . . 0.001503

jacob, non hispanic white male. 30 years old.

probability that jacob lives to be 30 years old.

since the given probabilities are probabilities of dying, i think we simply subtract it from 1 to get the probability of living. we will use the probability of non hispanic white male.

probability of living to be 30 y.o.

29 - 30 : 1 - 0.001477 = 0.998523

30 - 31 : 1 - 0.001503 = 0.998497