What is the difference between the 2007 power of -2 and the 2008 power of -2 2007 Power of -2 minus 2008 power of -2

What is the difference between the 2007 power of -2 and the 2008 power of -2 2007 Power of -2 minus 2008 power of -2

(-2)^2007-(-2)^2008
=-2^2007-2^2008
=-2^2007-2*2^2007
=-3*2^2007

What is the 2006 power of [-2]+ the 2007 power of [-2]

2006 Power of [-2]+2007 of [-2]
=2^2006-2^2007
=2^2006-2*2^2006
=-2^2006

[-2]2006 Power +[-2]2007
=2^2006-2^2007
=2^2006-2*2^2006
=-2^2006