化简 (2(1.9)+1)/(log_{2)(1.9)}

解答

化简

\frac{2 ( 1.9 ) + 1}{lo g _{2} ( 1.9 )}

\frac{24}{5 ( lo g _{2} ( 19 ) - 1 - lo g _{2} ( 5 ) )}

十进制

5.18358 \dots

求解步骤

\frac{2 ( 1.9 ) + 1}{lo g _{2} ( 1.9 )}

使用法则:

(a) = a

(1.9) = 1.9

= \frac{2 \cdot 1.9 + 1}{lo g _{2} ( 1.9 )}

2 \cdot 1.9 + 1 = 4.8

= \frac{4.8}{lo g _{2} ( 1.9 )}

lo g_{2} (1.9) = lo g_{2} (19) - 1 - lo g_{2} (5)

= \frac{4.8}{lo g _{2} ( 19 ) - 1 - lo g _{2} ( 5 )}

\frac{4.8}{lo g _{2} ( 19 ) - 1 - lo g _{2} ( 5 )} = \frac{48}{10 ( lo g _{2} ( 19 ) - 1 - lo g _{2} ( 5 ) )}

= \frac{48}{10 ( lo g _{2} ( 19 ) - 1 - lo g _{2} ( 5 ) )}

消掉

\frac{48}{10 ( lo g _{2} ( 19 ) - 1 - lo g _{2} ( 5 ) )} : \frac{24}{5 ( lo g _{2} ( 19 ) - 1 - lo g _{2} ( 5 ) )}

= \frac{24}{5 ( lo g _{2} ( 19 ) - 1 - lo g _{2} ( 5 ) )}

e x p an d (x^{2} - 2 x - 3) (2 x^{2} + 4 x - 5)

e x p an d (2 x^{3} - y^{3})^{2}

f a c t or 2 x^{3} - x^{2} - 20 x + 10

s im pl i f y \frac{1}{x} - \frac{1}{x + 3}

f a c t or a^{2} + 33 a + 252