Question 1176257
{{{H(t) = 120+55e^(-t/30)*cos(t*pi/4)}}}

Find her height at

 {{{t= 4 }}}


{{{H(4) = 120+55e^(-4/30)*cos(4*pi/4))}}}

{{{H(4) = 120+55e^(-2/15)*cos(pi)}}} ........{{{cos(pi)=-1}}}

{{{H(4) = 120+55e^(-2/15)*(-1) }}}

{{{H(4) = 120-55e^(-2/15)}}}

{{{H(4) = 120-48.1345326}}}

{{{H(4) = 71.87}}}


{{{t=8 }}}

{{{H(8) = 120+55e^(-8/30)*cos(8*pi/4)}}}

{{{H(8) = 120+55e^(-4/15)*cos(2*pi)}}}............{{{cos(2*pi)=1}}}

{{{H(8) = 120+55e^(-4/15)*1}}}

{{{H(8) = 120+42.12605861}}}

{{{H(8) = 162.13}}}


{{{t=12}}}

{{{H(12) = 120+55e^(-12/30)*cos(12*pi/4)}}}

{{{H(12) = 120+55e^(-2/5)*cos(3*pi)}}}............{{{cos(3*pi)=-1}}}

{{{H(12) = 120+55e^(-2/5)*(-1)}}}

{{{H(12) = 120-36.86760253}}}

{{{H(12) = 83.13}}}