1)
3 ^ ( 2y - 1 ) + 3 ^ ( 2y - 2 ) - 3 ^ ( 2y - 4 ) = 315
3 ^ 2y * ( 3 ^ - 1 + 3 ^ - 2 - 3 ^ - 4 ) = 315
3 ^ 2y * ( ( 1/3 ) + ( 1/9 ) - ( 1/81 ) ) = 315
3 ^ 2y * ( ( 27/81 ) + ( 9/81 ) - ( 1/81 )) = 315
3 ^ 2y = 315 : ( 35/81 )
3 ^ 2y = 729
3 ^ 2y = 3 ^ 6
2y = 6
y = 3
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2)
2 ^ ( X + 1 ) + 3 * 2 ^ ( X - 1 ) - 5 * 2 ^ X + 6 = 0
2 ^ X * ( 2 + 3 * 0,5 - 5 ) + 6 = 0
2 ^ X * ( - 1,5 ) = - 6
2 ^ X = - 6 : - 1,5
2 ^ X = 4
2 ^ X = 2 ^ 2
X = 2