A function $f ( x )$ that is differentiable on the entire set of real numbers satisfies the following conditions. What is the value of $f ( - 1 )$? [4 points] (가) For all real numbers $x$, $$2 \{ f ( x ) \} ^ { 2 } f ^ { \prime } ( x ) = \{ f ( 2 x + 1 ) \} ^ { 2 } f ^ { \prime } ( 2 x + 1 ).$$ (나) $f \left( - \frac { 1 } { 8 } \right) = 1 , f ( 6 ) = 2$
(1) $\frac { \sqrt [ 3 ] { 3 } } { 6 }$
(2) $\frac { \sqrt [ 3 ] { 3 } } { 3 }$
(3) $\frac { \sqrt [ 3 ] { 3 } } { 2 }$
(4) $\frac { 2 \sqrt [ 3 ] { 3 } } { 3 }$
(5) $\frac { 5 \sqrt [ 3 ] { 3 } } { 6 }$