2^(2x+1)-2^(x+2)-2^x <=3</p>
(2^(2x)) *2 - (2^x) *(2^2) -(2^x) -3 <=0</p>
2*(2^(2x)) -5*(2^x) -3 <=0|t=2^x</p>
2t^2-5t-3<=0</p>
D=49
t1=3, t2=-0,5
2(t-3)(t+0,5)<=0</p>
+ - +
----------[-0,5]---------[3]--------
-0,5<= t <=3</p>
-0,5<= 2^x <=3, но 2^x>0
0< 2^x <=3</p>
x<=log_2{3}</p>