I3.1 If $a$ is the remainder when $2 x^{3}-3 x^{2}+x-1$ is divided by $x+1$, find $a$.
I3.2 If $b \mathrm{~cm}^{2}$ is the total surface area of a cube of side $(8+a) \mathrm{cm}$, find $b$.
I3.3 One ball is taken at random from a bag containing $b+4$ red balls and $2 b-2$ white balls.
I3.4 If $\sin \theta=x\left(90^{\circ}<\theta<180^{\circ}\right)$ and $\tan \left(\theta-15^{\circ}\right)=y$, find $y$.
$$
a=2(-1)^{3}-3(-1)^{2}-1-1=-7
$$

Similar Questions: 1984 FG9.2, 1985 FSI. 2
$$
\begin{array}{l}
8+a=1 \\
b=6
\end{array}
$$

If $x$ is the probability that the ball is white, find $x$.
There are $b+4=10$ red balls and $2 b-2=10$ white balls
$$
\begin{array}{l}
x=\frac{1}{2} \\
\sin \theta=\frac{1}{2} \\
\Rightarrow \theta=150^{\circ} \\
y=\tan \left(\theta-15^{\circ}\right)=\tan 135^{\circ}=-1
\end{array}
$$