• The Basic Integration Formulas
1. ∫ du = u + C The integral of a differential variable u is u plus C
2. ∫ a du = a ∫ du The integral of a constant and a differential variable u
3. ∫ ( u +/- v ) du = ∫ u du +/- ∫ v du The integral of sum and difference
n+1
4. ∫ u du = u n+1 + C The power formula
n+1
PRACTICE PROBLEMS
1. Integrate ( 3x2 – 5 ) dx 2. Integrate ( x 8 – 4 x3 – x ) dx
3. Integrate ( x x1/2 - 5 )2 dx 4. Integrate ( x3 – 1 ) dx
x–1
5. Integrate ( x3 + 2x2 + x )1/2 dx
• The Integral of Logarithmic Functions
The formula ∫ du / u = ln u + C involves a numerator which is the derivative of the
denominator u represents any function involving any independent variable. The formula is
meaningless when u is negative, since the logarithms of negative numbers have not been
defined.
PRACTICE PROBLEMS:
1. Integrate ( 2x – 7 ) dx 2. Integrate ( 3 – 4x ) dx
4x2 – 6x + 20 x2 – 7x + 10
3. Integrate ( 4x2 – 8x – 9 ) dx 4. Integrate ( y2 +y ) dy
y–1 2x + 1
5. Integrate dy / y ( 1 + y2 ) 6. Integrate ( 1 – 3x )2 dx
7. Integrate cos t dt 8. Integrate ( x2 – 3 ) dx
3 + 3 sin t x3 – 9x + 5
9. Integrate ( x3 – 2x2 + 3 ) dx 10. Integrate dx / x ( x3 + 1 )
x–1
• The Integral of Exponential Function
Formulas:
1. ∫ a u du = ( a u / ln a ) + C provided a is greater than 0 and not equal to 1.
2. ∫ e u du = e u + C
PRACTICE PROBLEMS
1. Integrate ( 2 + e x ) dx 6. Integrate e – x /2 dx
ex
2. Integrate 3 x e x dx 7. Integrate e 2x dx
1 + ex
3. Integrate ( e x + e –x ) 2 dx 8. Integrate dy / 1 + ey
4. Integrate e x ( 1 + e x ) ½ dx 9. Integrate e 2x dx
1 + ex
5. Integrate ( 10 3x ) ½ dx 10. Integrate ( 2 – e –t ) 2 dt
• The Integral of Trigonometric Functions
The basic formulas for integration involving trigonometric functions are stated in terms of
appropriate pairs of functions. However, many trigonometric integrals can evaluated after the
transformations of the integrand, making use only of the familiar trigonometric formulas.
Trigonometric identities are employed to reduce the integrals to integrable forms.
PRACTICE PROBLEMS
1. Integrate ( 1 – cos x ) dx 6. Integrate cos3 x dx
sin 2 x 1 – sin x
2. Integrate ( cos 2 x ) dx 7. Integrate ( tan x – 1 )2 dx
1 + sin x
3. Integrate ( 1 – cos 2 x ) dx 8. Integrate ( sin3 y + cos3 y ) dy
1 + cos 2 x
4. Integrate ( sin x + 2 cos x )2 dx 9. Integrate ( sin3 x sin3 2x ) dx
sin x
5. Integrate ( sin2 x dx ) 10. Integrate ( sin5 y ) dy
1 – cos x cos2 y