[[input:ans1]]
[[input:ans1]] [[validation:ans1]]
[[input:ans2]] [[validation:ans2]]
[[input:ans3]] [[validation:ans3]]
[[input:ans4]] [[validation:ans4]]
[[input:ans5]] [[validation:ans5]]
[[input:ans7]] [[validation:ans7]]
[[input:ans10]] [[validation:ans10]]
[[input:ans15]] [[validation:ans15]]
[[input:ans20]] [[validation:ans20]]
[[input:ans1]]
[[input:ans1]]
[[input:ans1]]
[[input:ans1]]
[[input:ans1]]
[[input:ans1]]
[[input:ans1]]
1. Write down an equation which relates the side lengths to the area of the rectangle.
[[input:ans1]] [[validation:ans1]] [[feedback:eq]]
2. Solve your equation. Enter your answer as a set of numbers.
[[input:ans2]] [[validation:ans2]] [[feedback:sol]]
3. Hence, find the length of the shorter side.
[[input:ans3]] cm [[validation:ans3]] [[feedback:short]]
[[input:ans1]] [[validation:ans1]]
]]>\[ {@A@}.{@B@} = {@C@} = {@D@}.\]
]]>\[ f(x) :=\left\{ \begin{array}{ll} {@f0@} & \mbox{for } x\leq {@x0@}, \\ p(x) & \mbox{for } {@x0@} < x < {@x1@}, \\ {@f1@} & \mbox{for } {@x1@}\leq x.\end{array} \right. \]
{@plot(pg,[x,(x0-3),(x1+3)],[y,-3,3])@}
Find the cubic polynomial \(p(x)\) which makes \(f(x)\) continuously differentiable.
\(p(x)=\)[[input:ans1]]
\[ p({@x0@})={@subst(x=x0,f0)@}.\]
\[ p({@x1@})={@subst(x=x1,f1)@}.\]
\[ p'({@x0@})={@subst(x=x0,diff(f0,x))@}.\]
\[ p'({@x1@})={@subst(x=x1,diff(f1,x))@}.\]
If we define \(p(x)\) to be the cubic
\[ p(x) = a_3 x^3 + a_2 x^2 + a_1 x + a_0,\]
We then set up the matrix equation
\[ {@CS@} {@CV@} = {@CT@} \]
Solving this gives the coefficients, from which we get the polynomial.
{@ta@}.
]]>{@plot([pg,anspt],[x,(x0-3),(x1+3)],[y,-3,3])@}
]]>\(|z^{@n@}|=\)[[input:ans1]] [[validation:ans1]] [[feedback:prt1]]
and \(\arg(z^{@n@})=\)[[input:ans2]] [[validation:ans2]] [[feedback:prt2]]
]]>\[ {@q^n@} ={@a^n@} e^{@b*n*%i*%pi@}.\]
Recall that
\[ e^{i\theta} = \cos(\theta)+i\sin(\theta).\]
Working with the principle argument \(0\leq \theta \leq 2\pi\) gives us
\[ {@q^n@} = {@a^n@} e^{@b*n*%i*%pi@} = {@a^n@} e^{@ev(b*n,simp)*%i*%pi@} = {@a^n@} e^{@p*%i*%pi@}.\]
]]>2. Give an example of an even function. \(f_2(x)=\) [[input:ans2]]. [[validation:ans2]] [[feedback:even]]
3. Give an example of a function which is odd and even. \(f_3(x)=\) [[input:ans3]]. [[validation:ans3]] [[feedback:oddeven]]
4. Is the answer to 3. unique? [[input:ans4]] (Or are there many different possibilities.) [[validation:ans4]] [[feedback:unique]]
]]>Solve {@first(ta)@}, by factoring and working line by line. Leave your answer in the form \({@v@}=\cdots \mbox{ or } {@v@}=\cdots\) in fully simplified form.
[[input:ans1]] [[validation:ans1]]
]]>[[input:ans1]]