What is the largest value of x which satisfies
9 x = 3 x ?
It is neither a linear function nor an exponential function If you solve it, give us your solution, please.
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The intercept furthest right.
Do not doubt. For y = 9 x and y = 3^x,
At x = 0, 3^x > 9 x such that 1 > 0;
At x = 1, 9 x > 3^x such that 9 > 3;
At x = 2, 9 x > 3^x such that 18 > 9;
At x = 3, 3^x = 9 x such that 27 = 27;
At x = 4, 3^x > 9 x such that 81 > 36;
d y/ d x = 9 and d y / d x = (Ln 3) 3^x respectively where (Ln 3) 3^x > 9 at x >= 3+.
Largest value presumed real x only.
There are two intersect points, one at x = 0.127869 and another one at x = 3 only. Therefore, the largest value of x is 3.
9 x = 3 x . . . . . . . . . . ( A ) L e t " 3 " i s a n s w e r C h e c k i n g . P u t t i n g x = 3 i n ( A ) 9 ( 3 ) = 3 ( 3 ) = > 2 7 = 2 7 S a t i s f y
Same way of thinking here
Guess and check really. 2 and 1 don't work but 3 works because 9*3 is the same thing as 3^3
Easy just use log (3) 3is the base
(9)(3)=27 (3)(3)(3)=27 so x=3 after 3 no other number can be the value of x
9x=3^x -> x * 3^2= 3^x-> x=3 ^(x-2)-> x=3
9*3=27 and 3^3=27 hence x=3
9 = 3^3; 9x = 3^3*x; so question is 3^2 * x = 3^x, assume x = 3^y, then question becomes 3^(2+y) = 3^(3^y) == 3^(2+y) = 3^(3y); 2 + y = 3y, y = 1, and follows x = 3.
The best answer so far! Just need to correct into: "9 = 3^2; 9x = 3^2*x; so question is 3^2 * x = 3^x, assume x = 3^y, then question becomes 3^(2+y) = 3^(3^y) ==> 3^(2+y) = 3^(3y) ==> 2 + y = 3y, y = 1, and follows x = 3."
9x= 3^2 *x why it becomes 3^(2+y) not (3^2)+y ? Can u explain this one?
9x3 = 3³--> 9+9+9=3x3x3 --> 27 = 27 --> Thus, in the Naturals numbers three is the single answer...
Not different from Gowthaman's solution. You've simply shown us that 3 works, and used trial & error. And this is not a proof that this is the only solution in the natural numbers, although it's quite clear that it is if you observe how quickly the value of the RHS in x = 3 x − 2 rises compared to the LHS.
How can we know this is a unique solution? You haven't posted any solution btw, you've just showed us that 3 works, but the OP is searching for a solution that doesn't involve trial & error.
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In fact, that is not the only solution. Another solution is around 0 . 1 3 .
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Well, I'm reporting this question then, since there are multiple ways of answering it.
This question can be solved if you plot the graphs of y=9x and y=3^x separately and check for intersection points,one can find that both graphs intersect only at one possible point i.e. 3.
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They also intersect at around 0 . 1 2 7 8 6 9 . These two are the only points they intersect at, though.
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Graph the two functions 9x and 3^x and look for where the two intercept.