2*25^x =1+5^x
To solve this
equation, we put 5^x = y.
Then 25^x = (5^2)x = (5^x)^2 =
y^2.
So now we can rewrite the given equation
as:
2*y^2 =1+y
2y^2 -y -1 =
0
(2y+1)(y-1) = 0
2y+1 = 0 or
y-1 = 0.
y -1 = 0 gives: y = 1.
Or
5^x = 1 5^0
x =
0.
2y+1 = 0 gives: y = -1/2..
Or
5^x = -1/2. Thereis nor real solution. as for all real
x, 5^x > 0.
Therefore there is only one real
solution , that is , x = 0.
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