a, \(f\left(x\right)=2x^4-x^3+4x^2-x\)
\(\Rightarrow f'\left(x\right)=\left(2x^4-x^3+4x^2-x\right)'\)
\(=\left(2x^4\right)'-\left(x^3\right)'+\left(4x^2\right)'-\left(x\right)'\)
\(=2.4x^3-3x^2+4.2x-1\)
\(=8x^3-3x^2+8x-1\)
b, \(f\left(x\right)=2sinx\)
\(\Rightarrow f'\left(x\right)=\left(2sinx\right)'=2cosx\)
c, \(f\left(x\right)=\dfrac{3x^2+2x-5}{x}\)
\(\Rightarrow f'\left(x\right)=\left(\dfrac{3x^2+2x-5}{x}\right)'\)
\(=\left(3x+2-\dfrac{5}{x}\right)'\)
\(=\left(3x\right)'+\left(2\right)'-\left(\dfrac{5}{x}\right)'\)
\(=3+0+\dfrac{5}{x^2}=\dfrac{5}{x^2}+3\)
Đúng 0
Bình luận (0)
