$()(2$ points$)(+2)$

Q$2)$

i$)$Find values of the constants $a_{?}$ and $b_{?}$ that will make the function f continuous everywhere.

$f(x)=\{\begin{array}{cc}5x+a,& x<mn>2</mn>\\ 2x^2+2a-1,& 2x<mn>4</mn>\\ x^3-bx-7,& x4\end{array}$

ii$)$ solve for $t$ :

$e^{2t}-e^t=a-b+\frac{8}{}++\frac{15}{26}$

where