Question
If f is the function given by \(f(x)=\frac{4}{x}+5x-1\) ,then f‘(2) =
A 4
B 6
C 7
D 11
▶️Answer/Explanation
Ans:A
Question
If f(x)=x,then \(f{}'(5)=\)
A 0
B \(\frac{1}{5}\)
C 1
D 5
E \(\frac{25}{2}\)
▶️Answer/Explanation
Ans:C
Question
If \(f(x)=x^{\frac{3}{2}}\) , then \({f}’\)(4)
(A) –6 (B) –3 (C) 3 (D) 6 (E) 8
▶️Answer/Explanation
Ans:C
\(f'(x)=\frac{3}{2}x^{\frac{1}{2}}; f'(4)^{\frac{3}{2}}.4^{\frac{1}{2}}=\frac{3}{2}.2=3\)
Question
If \(f(x)=\sqrt{x}+\frac{3}{\sqrt{x}}\),then f(4)=
A \(\frac{1}{10}\)
B \(\frac{5}{16}\)
C 1
D \(\frac{7}{2}\)
E \(\frac{49}{4}\)
▶️Answer/Explanation
Ans:A