定义域 f(x)=sqrt(25-(x+7)^2),x<=-2

解答

定义域

f (x) = 25 - (x + 7)^{2}, x \leq - 2

- 12 \leq x \leq - 2

间隔符号

[- 12, - 2]

求解步骤

设定义域为给定区间

x \leq - 2

对于根式找到非负值:

- 12 \leq x \leq - 2

将实数值区域与定义域合并:

- 12 \leq x \leq - 2 and x \leq - 2

- 12 \leq x \leq - 2

r an g e \frac{3 x - 8}{7 - x}

in t erce pt s f (x) = \frac{x ( x + 1 ) ( x - 6 )}{x + 8}

d o main f (x) = \frac{x}{2 x - 5}

d o main \frac{5 x - 4}{( x - 7 ) ^{2}}

a sy m pt o t es f (x) = \frac{6 x ^{2} + 7}{8 x + 6}