SEARCH THIS BLOG :-)
Monday, 20 February 2006
Integration By Parts - Several Examples.
THE FORMULA FOR INTEGRATION BY PARTS
Let $u(x), v(x)$ be two functions of $x$.
$$ \int u(x) v'(x)\,dx=u(x) v(x)-\int u'(x) v(x)\,dx$$
or the 'quick formula'
$$ \int uv'=uv-\int u'v$$
Let $u(x), v(x)$ be two functions of $x$.
$$ \int u(x) v'(x)\,dx=u(x) v(x)-\int u'(x) v(x)\,dx$$
or the 'quick formula'
$$ \int uv'=uv-\int u'v$$
[Remark: This is like the product rule for derivatives]
Thursday, 16 February 2006
Prove the series result - exponential series $$\left( \sum_{k=0}^\infty {u^k\over k!} \right) \left( \sum_{l=0}^\infty {v^l\over l!} \right) = \sum_{m=0}^\infty {(u+v)^m\over m!} $$ where $u,v\in C$.
Prove the series result - exponential series
$$\left( \sum_{k=0}^\infty {u^k\over k!} \right) \left( \sum_{l=0}^\infty {v^l\over l!} \right)
= \sum_{m=0}^\infty {(u+v)^m\over m!} $$
where $u,v\in C$.
Wednesday, 15 February 2006
College Algebra : Logarithms and Exponents manipulation and Graphs questions
QUESTIONS:
Solve each logarithmic equation.
Q14. $\displaystyle x=\log_8 \sqrt[4]{8}$
Q20. $\displaystyle x=12^{\log_{12}5}$
Q24. $\displaystyle \log_x {1 \over 16}=-2$
Sketch the graph of $f(x)=\log_2 x$. Then refer to it to graph these functions.
Q34. $\displaystyle f(x)=\log_2(x+3)$
Q42. $\displaystyle f(x)=\log_2{x\over 2}$
Solve each logarithmic equation.
Q14. $\displaystyle x=\log_8 \sqrt[4]{8}$
Q20. $\displaystyle x=12^{\log_{12}5}$
Q24. $\displaystyle \log_x {1 \over 16}=-2$
Sketch the graph of $f(x)=\log_2 x$. Then refer to it to graph these functions.
Q34. $\displaystyle f(x)=\log_2(x+3)$
Q42. $\displaystyle f(x)=\log_2{x\over 2}$
Q50. Sketch the graph $\displaystyle f(x)=\log_2x^2$
Use the properties of logarithms to rewrite each expression. Simplify the result if possible. Assume all variables represent positive real numbers.
Q58. $\displaystyle \log_3{4p\over q}$
Q61. $\displaystyle \log_4{2x+5y}$
Q64. $\displaystyle \log_p\sqrt[3]{{m^5 n^4\over t^2}}$
Write each expression as a single logarithm with coefficient $1$. Assume all variables represent positive real numbers.
Q66. $\displaystyle (\log_bk-\log_bm)-\log_ba$
Q68. $\displaystyle {1\over 2} \log_yp^3q^4 -{2\over 3} \log_y p^4q^3$
Q70. $\displaystyle \log_b(2y+5)-{1\over 2} \log_b(y+3)$
Use the properties of logarithms to rewrite each expression. Simplify the result if possible. Assume all variables represent positive real numbers.
Q58. $\displaystyle \log_3{4p\over q}$
Q61. $\displaystyle \log_4{2x+5y}$
Q64. $\displaystyle \log_p\sqrt[3]{{m^5 n^4\over t^2}}$
Write each expression as a single logarithm with coefficient $1$. Assume all variables represent positive real numbers.
Q66. $\displaystyle (\log_bk-\log_bm)-\log_ba$
Q68. $\displaystyle {1\over 2} \log_yp^3q^4 -{2\over 3} \log_y p^4q^3$
Q70. $\displaystyle \log_b(2y+5)-{1\over 2} \log_b(y+3)$
SOLUTIONS ==================
Labels:
Algebra,
College algebra,
Exponentials,
Exponents,
high school,
Logarithms.,
Single log
Monday, 13 February 2006
Complex functions & Limits: (2) Let $a,b$ be complex constants. Show that $$\lim_{z\rightarrow z_0} (az+b)=az_0+b$$ (7) Use the definition of limit to prove that if $\displaystyle \lim_{z\rightarrow z_0} f(z)=w_0$ then $$\displaystyle \lim_{z\rightarrow z_0} \left|f(z)\right|=\left|w_0\right|$$
QUESTIONS:
(2) Let $a,b$ be complex constants. Show that $$\lim_{z\rightarrow z_0} (az+b)=az_0+b$$
Friday, 10 February 2006
Complex Functions (Differentiability) Show that $f'(z)$ does not exist at any point $z$ when (a) $f(z)=\bar{z}$ (b) $f(z)=Re (z)$ (c) $f(z)=Im (z)$
QUESTION: Show that $f'(z)$ does not exist at any point $z$ when
(a) $f(z)=\bar{z}$
(b) $f(z)=Re (z)$
(c) $f(z)=Im (z)$
(a) $f(z)=\bar{z}$
(b) $f(z)=Re (z)$
(c) $f(z)=Im (z)$
APPENDIX: SOME ADDITIONAL SUPPORT FILES.
Thursday, 9 February 2006
LU Decomposition, Matrices. Find a matrix $A$ that admits NO $LU$ decomposition, even if we only require that $L$ is lower triangular (not necessarily unit) and $U$ is upper triangular. Justify your answer.
QUESTION: Find a matrix $A$ that admits NO $LU$ decomposition, even if we only require that $L$ is lower triangular (not necessarily unit) and $U$ is upper triangular. Justify your answer.
Wednesday, 1 February 2006
Integration using substitution. (5) $\displaystyle\int_{-1}^1 {e^{\arctan x} \over 1+x^2} dx$ (12) $\displaystyle\int\sin x \cos(\cos x) dx$ (15) $\displaystyle\int_0^{1/2} {x\over \sqrt{1-x^2}} dx$ (18) $\displaystyle\int {e^{2x}\over 1+e^{4x}} dx$ (19) $\displaystyle\int e^{x+e^x} dx$ (26) $\displaystyle\int {3x^2-2\over x^3-2x-8} dx$ (27) $\displaystyle\int \cot x \ln (\sin x) dx$ (43) $\displaystyle\int e^x \sqrt{1+e^x} dx$ (34) $\displaystyle\int_{\pi/4}^{\pi/2} {1+4\cot x\over 4-\cot x} dx$
QUESTIONS: Integration using substitutions.
(5) $\displaystyle\int_{-1}^1 {e^{\arctan x} \over 1+x^2} dx$
(12) $\displaystyle\int\sin x \cos(\cos x) dx$
(15) $\displaystyle\int_0^{1/2} {x\over \sqrt{1-x^2}} dx$
(18) $\displaystyle\int {e^{2x}\over 1+e^{4x}} dx$
(19) $\displaystyle\int e^{x+e^x} dx$
(26) $\displaystyle\int {3x^2-2\over x^3-2x-8} dx$
(27) $\displaystyle\int \cot x \ln (\sin x) dx$
(43) $\displaystyle\int e^x \sqrt{1+e^x} dx$
(34) $\displaystyle\int_{\pi/4}^{\pi/2} {1+4\cot x\over 4-\cot x} dx$
SOLUTIONS
(5) $\displaystyle\int_{-1}^1 {e^{\arctan x} \over 1+x^2} dx$
(12) $\displaystyle\int\sin x \cos(\cos x) dx$
(15) $\displaystyle\int_0^{1/2} {x\over \sqrt{1-x^2}} dx$
(18) $\displaystyle\int {e^{2x}\over 1+e^{4x}} dx$
(19) $\displaystyle\int e^{x+e^x} dx$
(26) $\displaystyle\int {3x^2-2\over x^3-2x-8} dx$
(27) $\displaystyle\int \cot x \ln (\sin x) dx$
(43) $\displaystyle\int e^x \sqrt{1+e^x} dx$
(34) $\displaystyle\int_{\pi/4}^{\pi/2} {1+4\cot x\over 4-\cot x} dx$
SOLUTIONS
Subscribe to:
Posts (Atom)