how to solve $log (x+1) +3 = frac2x+2$
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From the Jan 17 NYS Algebra 2 Regents, a multiple choice question with seemingly no satisfying answer:
"When $g(x) = frac2x+2$ and $h(x) = log (x+1)+3$ are graphed on the same set of axes, which coordinates best approximate their point of intersection?"
$$(1) (-0.9, 1.8)$$
$$(2) (-0.9, 1.9)$$
$$(3) (1.4, 3.3)$$
$$(4) (1.4, 3.4)$$
Plugging in an $x$ value of $-0.9$ yields $y$ values of $1.8181$... and $2$, respectively, so neither answers # 1 nor # 2 are 'best,' and an $x$-value of $1.4$ does not work at all for $g(x)$.
On Desmos I obtained an approximation of $(-.927, 1.8638)$ as the intersection of the graphs, i.e., approximately the 'solution.'
Here's my real question: can this type of equation, $frac2x+2 = log(x+1)+3$ actually be solved algebraically; and if so, how?
Many thanks, as always.
logarithms
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up vote
1
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From the Jan 17 NYS Algebra 2 Regents, a multiple choice question with seemingly no satisfying answer:
"When $g(x) = frac2x+2$ and $h(x) = log (x+1)+3$ are graphed on the same set of axes, which coordinates best approximate their point of intersection?"
$$(1) (-0.9, 1.8)$$
$$(2) (-0.9, 1.9)$$
$$(3) (1.4, 3.3)$$
$$(4) (1.4, 3.4)$$
Plugging in an $x$ value of $-0.9$ yields $y$ values of $1.8181$... and $2$, respectively, so neither answers # 1 nor # 2 are 'best,' and an $x$-value of $1.4$ does not work at all for $g(x)$.
On Desmos I obtained an approximation of $(-.927, 1.8638)$ as the intersection of the graphs, i.e., approximately the 'solution.'
Here's my real question: can this type of equation, $frac2x+2 = log(x+1)+3$ actually be solved algebraically; and if so, how?
Many thanks, as always.
logarithms
1
Maybe you want to try the "Lambert W Function" for reference.
– Evan William Chandra
Jul 23 at 4:49
Only hope is numeric. "Lambert W Function" will not help you in any way.
– Mariusz Iwaniuk
Jul 23 at 8:19
Can't see a closed form solution but consider $log(x+1)-dfrac2x+2+3 = 0$ and apply newtons method to find $x$
– Warren Hill
Jul 23 at 14:38
add a comment |Â
up vote
1
down vote
favorite
up vote
1
down vote
favorite
From the Jan 17 NYS Algebra 2 Regents, a multiple choice question with seemingly no satisfying answer:
"When $g(x) = frac2x+2$ and $h(x) = log (x+1)+3$ are graphed on the same set of axes, which coordinates best approximate their point of intersection?"
$$(1) (-0.9, 1.8)$$
$$(2) (-0.9, 1.9)$$
$$(3) (1.4, 3.3)$$
$$(4) (1.4, 3.4)$$
Plugging in an $x$ value of $-0.9$ yields $y$ values of $1.8181$... and $2$, respectively, so neither answers # 1 nor # 2 are 'best,' and an $x$-value of $1.4$ does not work at all for $g(x)$.
On Desmos I obtained an approximation of $(-.927, 1.8638)$ as the intersection of the graphs, i.e., approximately the 'solution.'
Here's my real question: can this type of equation, $frac2x+2 = log(x+1)+3$ actually be solved algebraically; and if so, how?
Many thanks, as always.
logarithms
From the Jan 17 NYS Algebra 2 Regents, a multiple choice question with seemingly no satisfying answer:
"When $g(x) = frac2x+2$ and $h(x) = log (x+1)+3$ are graphed on the same set of axes, which coordinates best approximate their point of intersection?"
$$(1) (-0.9, 1.8)$$
$$(2) (-0.9, 1.9)$$
$$(3) (1.4, 3.3)$$
$$(4) (1.4, 3.4)$$
Plugging in an $x$ value of $-0.9$ yields $y$ values of $1.8181$... and $2$, respectively, so neither answers # 1 nor # 2 are 'best,' and an $x$-value of $1.4$ does not work at all for $g(x)$.
On Desmos I obtained an approximation of $(-.927, 1.8638)$ as the intersection of the graphs, i.e., approximately the 'solution.'
Here's my real question: can this type of equation, $frac2x+2 = log(x+1)+3$ actually be solved algebraically; and if so, how?
Many thanks, as always.
logarithms
edited Jul 23 at 4:30
Gonzalo Benavides
581317
581317
asked Jul 23 at 4:18


Victor Jaroslaw
212
212
1
Maybe you want to try the "Lambert W Function" for reference.
– Evan William Chandra
Jul 23 at 4:49
Only hope is numeric. "Lambert W Function" will not help you in any way.
– Mariusz Iwaniuk
Jul 23 at 8:19
Can't see a closed form solution but consider $log(x+1)-dfrac2x+2+3 = 0$ and apply newtons method to find $x$
– Warren Hill
Jul 23 at 14:38
add a comment |Â
1
Maybe you want to try the "Lambert W Function" for reference.
– Evan William Chandra
Jul 23 at 4:49
Only hope is numeric. "Lambert W Function" will not help you in any way.
– Mariusz Iwaniuk
Jul 23 at 8:19
Can't see a closed form solution but consider $log(x+1)-dfrac2x+2+3 = 0$ and apply newtons method to find $x$
– Warren Hill
Jul 23 at 14:38
1
1
Maybe you want to try the "Lambert W Function" for reference.
– Evan William Chandra
Jul 23 at 4:49
Maybe you want to try the "Lambert W Function" for reference.
– Evan William Chandra
Jul 23 at 4:49
Only hope is numeric. "Lambert W Function" will not help you in any way.
– Mariusz Iwaniuk
Jul 23 at 8:19
Only hope is numeric. "Lambert W Function" will not help you in any way.
– Mariusz Iwaniuk
Jul 23 at 8:19
Can't see a closed form solution but consider $log(x+1)-dfrac2x+2+3 = 0$ and apply newtons method to find $x$
– Warren Hill
Jul 23 at 14:38
Can't see a closed form solution but consider $log(x+1)-dfrac2x+2+3 = 0$ and apply newtons method to find $x$
– Warren Hill
Jul 23 at 14:38
add a comment |Â
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1
Maybe you want to try the "Lambert W Function" for reference.
– Evan William Chandra
Jul 23 at 4:49
Only hope is numeric. "Lambert W Function" will not help you in any way.
– Mariusz Iwaniuk
Jul 23 at 8:19
Can't see a closed form solution but consider $log(x+1)-dfrac2x+2+3 = 0$ and apply newtons method to find $x$
– Warren Hill
Jul 23 at 14:38