Can someone ask me some exponential equations where you change to quadratic (1 Viewer)

quickoats

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The questions like 4^x + 6^x = 9^x (which is what I'm assuming you're referring to) can't be solved unless there's a convenient trick (like the quadratic one).

Similar questions might be 4^x + 10^x = 25^x etc but you probably couldn't algebraically find a solution to 2^x + 3^x = 7^x.
 
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The questions like 4^x + 6^x = 9^x (which is what I'm assuming you're referring to) can't be solved unless there's a convenient trick (like the quadratic one).

Similar questions might be 4^x + 10^x = 25^x etc but you probably couldn't algebraically find a solution to 2^x + 3^x = 7^x.
Can you check my solution
 

A1La5

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Ok here is the solution
You don't need logarithms for this at all. It's just substitution, unless I misunderstood the particular type of question you wanted.
For the equation you attempted, the solutions are and .
 

vernburn

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Can you check my solution
You need to work on your setting out. Firstly you replace with without specifying. Furthermore, you should avoid stuff like "let ". You are better off choosing a different pronumeral to avoid confusion like "let ". You also left your answer as which doesn't make any sense! Good effort though.
 

A1La5

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Oh lol i made a simple mistake lol
I think the kind of question you wanted is something like: e^2x - 6e^x + 5 = 0.
Yeah, my bad on that. Still though, it never hurts to revise the basics before trying more.
 
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You need to work on your setting out. Firstly you replace with without specifying. Furthermore, you should avoid stuff like "let ". You are better off choosing a different pronumeral to avoid confusion like "let ". You also left your answer as which doesn't make any sense! Good effort though.
I replaced it to form the quadratic
 

Qeru

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You don't need logarithms for this at all. It's just substitution, unless I misunderstood the particular type of question you wanted.
For the equation you attempted, the solutions are and .
Over the real numbers ofcourse, more generally
 
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You need to work on your setting out. Firstly you replace with without specifying. Furthermore, you should avoid stuff like "let ". You are better off choosing a different pronumeral to avoid confusion like "let ". You also left your answer as which doesn't make any sense! Good effort though.
So should i use U instead of x
 

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