Question

2 la puterea x plus 2 la puterea x plus 1 plus 2 la puterea x plus 2 mai mic decât 112

Answer 1

2^x+2^(x+1)+2^(x+2)<112
2^x+2^x*2+2^x*2^2<112
2^x(1+2+4)<112
2^x*7<112
2^x<112÷7
2^x<16
2^x<2^4
x<4
x apartine{0,1,2,3}

Answer 2

$2^{x}~+~2^{x+1}~+~2^{x+2}~<~112$
$2^{x}~+~2^{x}*2~+~2^{x}*2^{2}$
$2^{x}(1+2+2^{2})~<~112$
$2^{x}(1+2+4)~<~112$
$2^{x}*7~<~112$
$2^{x}~<~16$
$x<4$
x € {0, 1, 2, 3}