What is the derivative of f(x) = x² + x?
A
2x
B
2x + 1
C
x + 2
D
x² + 1
Analysis & Theory
Using the sum rule: d/dx(x² + x) = d/dx(x²) + d/dx(x) = 2x + 1.
If f(x) = sin x + cos x, what is f'(x)?
A
cos x - sin x
B
cos x + sin x
C
-cos x + sin x
D
-sin x - cos x
Analysis & Theory
d/dx(sin x + cos x) = cos x - sin x.
The derivative of f(x) = e^x + ln x is:
A
e^x
B
1/x
C
e^x + 1/x
D
ln x + e^x
Analysis & Theory
d/dx(e^x + ln x) = d/dx(e^x) + d/dx(ln x) = e^x + 1/x.
Differentiate f(x) = 3x⁴ + 2x² + 7
A
12x³ + 4x + 7
B
12x³ + 4x
C
3x³ + x + 7
D
6x³ + 2x
Analysis & Theory
d/dx(3x⁴ + 2x² + 7) = 12x³ + 4x + 0 = 12x³ + 4x.
Which rule is used to differentiate f(x) = u(x) + v(x)?
A
Product Rule
B
Chain Rule
C
Sum Rule
D
Quotient Rule
Analysis & Theory
The sum rule states: d/dx[u(x) + v(x)] = u'(x) + v'(x).
Find d/dx of x³ + 5x² - x + 4
A
3x² + 10x - 1
B
3x² + 5x - 1
C
2x + 5x - 1
D
None of the above
Analysis & Theory
Differentiate term by term: 3x² + 10x - 1.
If f(x) = ln x + 1/x, then f'(x) is:
A
1/x + x
B
1/x - 1/x²
C
ln x - 1/x
D
None of these
Analysis & Theory
d/dx(ln x) = 1/x and d/dx(1/x) = -1/x², so f'(x) = 1/x - 1/x².
The sum rule in differentiation means:
A
d/dx(f + g) = f' - g'
B
d/dx(f + g) = f'g'
C
d/dx(f + g) = f' + g'
D
d/dx(f + g) = f + g
Analysis & Theory
The sum rule states the derivative of a sum is the sum of derivatives.
Differentiate f(x) = √x + 1/x
A
1/(2√x) - 1/x²
B
1/(2√x) + 1/x²
C
1/x + 1/x²
D
1/x - 1/x²
Analysis & Theory
d/dx(√x) = 1/(2√x), d/dx(1/x) = -1/x², so total is 1/(2√x) - 1/x².
If f(x) = x⁵ + 2x³ + x, then f'(x) is:
A
5x⁴ + 6x² + 1
B
5x⁴ + 2x² + 1
C
5x⁴ + 6x²
D
None of these
Analysis & Theory
Differentiate each term: d/dx(x⁵) = 5x⁴, d/dx(2x³) = 6x², d/dx(x) = 1.