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Find the value of x : (4)2x-1-(16)x-1=384 . . .

Question : Find the value of x : (4)2x-1-(16)x-1=384  


Doubt by Balvinder

Solution : 
(4)2x-1 - (16)x-1 = 384
(4)2x-1 - (42)x-1 = 384
(4)2x-1 - (4)2(x-1) = 384
(4)2x-1 - (4)2x-2 = 384
(4)2x-1 - (4)2x-1-1 = 384
(4)2x-1 - (4)2x-1.4-1 = 384

(4)2x-1 [1-1/4] = 384
(4)2x-1 [(4-1)/4] = 384
(4)2x-1 [3/4] = 384
(4)2x-1= (384×4)/3
(4)2x-1= 128×4
(4)2x-1= 512
(2²)2x-1=29
22(2x-1)=29
24x-2=29

equating the power of 2 both sides
4x-2=9
4x=9+2
4x=11
x=11/4