Answer:
The correct answer is option D. -126
Step-by-step explanation:
Points to remember
Composite functions
f(x) and g(x) be the functions then,
(f - g)(x) = f(x) - g(x)
To find the value of (m - n)(-5)
Let m(x) = x³ and n(x) = √ (6 + x)
(m - n)(x) = m(x) - n(x)
= x³ - √( 6 + x)
(m - n)(-5) = m(-5) - n(-5)
= x³ - √( 6 + x)
= (-5)³ - √( 6 + -5)
= -125 - √1
= -125 -1
= -126
The correct answer is option D. -126
