解答
log10(5)(3x2−3)−log10(5)(x+5)=1
解答
x=6log10(5)log10(5)+97log10(5)2+12log10(5),x=6log10(5)log10(5)−97log10(5)2+12log10(5)
+1
十进制
x=1.94749…,x=−1.61415…求解步骤
log10(5)(3x2−3)−log10(5)(x+5)=1
展开 log10(5)(3x2−3)−log10(5)(x+5):3log10(5)x2−log10(5)x−8log10(5)
3log10(5)x2−log10(5)x−8log10(5)=1
将 1para o lado esquerdo
3log10(5)x2−log10(5)x−8log10(5)−1=0
使用求根公式求解
x1,2=2⋅3log10(5)−(−log10(5))±(−log10(5))2−4⋅3log10(5)(−8log10(5)−1)
(−log10(5))2−4⋅3log10(5)(−8log10(5)−1)=97log10(5)2+12log10(5)
x1,2=2⋅3log10(5)−(−log10(5))±97log10(5)2+12log10(5)
将解分隔开x1=2⋅3log10(5)−(−log10(5))+97log10(5)2+12log10(5),x2=2⋅3log10(5)−(−log10(5))−97log10(5)2+12log10(5)
x=2⋅3log10(5)−(−log10(5))+97log10(5)2+12log10(5):6log10(5)log10(5)+97log10(5)2+12log10(5)
x=2⋅3log10(5)−(−log10(5))−97log10(5)2+12log10(5):6log10(5)log10(5)−97log10(5)2+12log10(5)
二次方程组的解是:x=6log10(5)log10(5)+97log10(5)2+12log10(5),x=6log10(5)log10(5)−97log10(5)2+12log10(5)