Difference between revisions of "009B Sample Final 2, Problem 1"

From Grad Wiki
Jump to navigation Jump to search
 
Line 9: Line 9:
 
::<math>\frac{d}{dx}\int_1^{\frac{1}{x}} \sin t~dt</math>
 
::<math>\frac{d}{dx}\int_1^{\frac{1}{x}} \sin t~dt</math>
  
{| class="mw-collapsible mw-collapsed" style = "text-align:left;"
+
<hr>
!Foundations: &nbsp;
+
[[009B Sample Final 2, Problem 1 Solution|'''<u>Solution</u>''']]
|-
 
|'''1.''' What does Part 2 of the Fundamental Theorem of Calculus say about &nbsp;<math style="vertical-align: -15px">\int_a^b\sec^2x~dx</math>&nbsp; where &nbsp;<math style="vertical-align: -5px">a,b</math>&nbsp; are constants?
 
|-
 
|
 
&nbsp; &nbsp; &nbsp; &nbsp; Part 2 of the Fundamental Theorem of Calculus says that
 
|-
 
|&nbsp; &nbsp; &nbsp; &nbsp; <math style="vertical-align: -15px">\int_a^b\sec^2x~dx=F(b)-F(a)</math>&nbsp; where &nbsp;<math style="vertical-align: 0px">F</math>&nbsp; is any antiderivative of &nbsp;<math style="vertical-align: 0px">\sec^2x.</math>
 
|-
 
|'''2.''' What does Part 1 of the Fundamental Theorem of Calculus say about &nbsp;<math style="vertical-align: -15px">\frac{d}{dx}\int_0^x\sin(t)~dt?</math>
 
|-
 
|
 
&nbsp; &nbsp; &nbsp; &nbsp; Part 1 of the Fundamental Theorem of Calculus says that
 
|-
 
|&nbsp; &nbsp; &nbsp; &nbsp; <math style="vertical-align: -15px">\frac{d}{dx}\int_0^x\sin(t)~dt=\sin(x).</math>
 
|}
 
  
'''Solution:'''
 
  
'''(a)'''
+
[[009B Sample Final 2, Problem 1 Detailed Solution|'''<u>Detailed Solution</u>''']]
  
{| class="mw-collapsible mw-collapsed" style = "text-align:left;"
 
!Step 1: &nbsp;
 
|-
 
|The Fundamental Theorem of Calculus has two parts.
 
|-
 
|'''The Fundamental Theorem of Calculus, Part 1'''
 
|-
 
|&nbsp; &nbsp; &nbsp; &nbsp;Let &nbsp;<math>f</math>&nbsp; be continuous on &nbsp;<math style="vertical-align: -5px">[a,b]</math>&nbsp; and let &nbsp;<math style="vertical-align: -14px">F(x)=\int_a^x f(t)~dt.</math>
 
|-
 
|&nbsp; &nbsp; &nbsp; &nbsp;Then, &nbsp;<math style="vertical-align: 0px">F</math>&nbsp; is a differentiable function on &nbsp;<math style="vertical-align: -5px">(a,b)</math>&nbsp; and &nbsp;<math style="vertical-align: -5px">F'(x)=f(x).</math>
 
|}
 
  
{| class="mw-collapsible mw-collapsed" style = "text-align:left;"
 
!Step 2: &nbsp;
 
|-
 
|'''The Fundamental Theorem of Calculus, Part 2'''
 
|-
 
|&nbsp; &nbsp; &nbsp; &nbsp;Let &nbsp;<math>f</math>&nbsp; be continuous on &nbsp;<math>[a,b]</math>&nbsp; and let &nbsp;<math style="vertical-align: 0px">F</math>&nbsp; be any antiderivative of &nbsp;<math>f.</math>
 
|-
 
|&nbsp; &nbsp; &nbsp; &nbsp;Then, &nbsp;<math style="vertical-align: -14px">\int_a^b f(x)~dx=F(b)-F(a).</math>
 
|}
 
 
'''(b)'''
 
 
{| class="mw-collapsible mw-collapsed" style = "text-align:left;"
 
!Step 1: &nbsp;
 
|-
 
|The Fundamental Theorem of Calculus Part 2 says that
 
|-
 
|&nbsp; &nbsp; &nbsp; &nbsp; <math>\int_0^1 \frac{d}{dx}\bigg(e^{\arctan(x)}\bigg)~dx=F(1)-F(0)</math>
 
|-
 
|where &nbsp;<math style="vertical-align: -5px">F(x)</math>&nbsp; is any antiderivative of &nbsp;<math style="vertical-align: -15px">\frac{d}{dx}\bigg(e^{\arctan(x)}\bigg).</math>
 
|-
 
|Thus, we can take
 
|-
 
|&nbsp; &nbsp; &nbsp; &nbsp;<math>F(x)=e^{\arctan(x)}</math>
 
|-
 
|since then <math style="vertical-align: -15px">F'(x)=\frac{d}{dx}\bigg(e^{\arctan(x)}\bigg).</math>
 
|}
 
 
{| class="mw-collapsible mw-collapsed" style = "text-align:left;"
 
!Step 2: &nbsp;
 
|-
 
|Now, we have
 
|-
 
|&nbsp; &nbsp; &nbsp; &nbsp; <math>\begin{array}{rcl}
 
\displaystyle{\int_0^1 \frac{d}{dx}\bigg(e^{\arctan(x)}\bigg)~dx} & = & \displaystyle{F(1)-F(0)}\\
 
&&\\
 
& = & \displaystyle{e^{\arctan(1)}-e^{\arctan(0)}}\\
 
&&\\
 
& = & \displaystyle{e^{\frac{\pi}{4}}-e^0}\\
 
&&\\
 
& = & \displaystyle{e^{\frac{\pi}{4}}-1.}
 
\end{array}</math>
 
|}
 
 
'''(c)'''
 
 
{| class="mw-collapsible mw-collapsed" style = "text-align:left;"
 
!Step 1: &nbsp;
 
|-
 
|Using the Fundamental Theorem of Calculus Part 1 and the Chain Rule, we have
 
|-
 
|&nbsp; &nbsp; &nbsp; &nbsp;<math>\frac{d}{dx}\int_1^{\frac{1}{x}} \sin t~dt=\sin\bigg(\frac{1}{x}\bigg)\frac{d}{dx}\bigg(\frac{1}{x}\bigg).</math>
 
|-
 
|
 
|}
 
 
{| class="mw-collapsible mw-collapsed" style = "text-align:left;"
 
!Step 2: &nbsp;
 
|-
 
|Hence, we have
 
|-
 
|&nbsp; &nbsp; &nbsp; &nbsp;<math>\frac{d}{dx}\int_1^{\frac{1}{x}} \sin t~dt=\sin\bigg(\frac{1}{x}\bigg)\bigg(-\frac{1}{x^2}\bigg).</math>
 
|-
 
|
 
|}
 
 
{| class="mw-collapsible mw-collapsed" style = "text-align:left;"
 
!Final Answer: &nbsp;
 
|-
 
|&nbsp; &nbsp;'''(a)'''&nbsp; &nbsp; See above
 
|-
 
|&nbsp; &nbsp;'''(b)'''&nbsp; &nbsp; <math>e^{\frac{\pi}{4}}-1</math>
 
|-
 
|&nbsp; &nbsp;'''(c)'''&nbsp; &nbsp; <math>\sin\bigg(\frac{1}{x}\bigg)\bigg(-\frac{1}{x^2}\bigg)</math>
 
|}
 
 
[[009B_Sample_Final_2|'''<u>Return to Sample Exam</u>''']]
 
[[009B_Sample_Final_2|'''<u>Return to Sample Exam</u>''']]

Latest revision as of 17:24, 2 December 2017

(a) State both parts of the Fundamental Theorem of Calculus.

(b) Evaluate the integral

(c) Compute


Solution


Detailed Solution


Return to Sample Exam