What is the expression for f(x)f(x)f, left parenthesis, x, right parenthesis when we rewrite \left(\dfrac{1}{49}\right) ^{x}\cdot \left(\dfrac{1}{7}\right)^{6x 11}( 49 1 ​ ) x ⋅( 7 1 ​ ) 6x 11 left parenthesis, start fraction, 1, divided by, 49, end fraction, right parenthesis, start superscript, x, end superscript, dot, left parenthesis, start fraction, 1, divided by, 7, end fraction, right parenthesis, start superscript, 6, x, plus, 11, end superscript as \left(\dfrac{1}{7}\right)^{f(x)}( 7 1 ​ ) f(x) left parenthesis, start fraction, 1, divided by, 7, end fraction, right parenthesis, start superscript, f, left parenthesis, x, right parenthesis, end superscript ? f(x)=