1983 年

$\dfrac{6}{x^2-9}-\dfrac{5}{x^2+x-6}=$

$\dfrac{\dfrac{1}{a^3}+\dfrac{1}{b^3}}{\dfrac{1}{a}+\dfrac{1}{b}}=$

If $x=\dfrac{y^2}{\sqrt{a^2+bz}}$, then $z=$

$(x^2y^{-1})\div\left(x^{\frac12}y^{-1}\right)^2=$

The H.C.F. of $a^3-1$ and $a^4-1$ is

When $\mathrm{f}(x)$ is divided by $(2x+1)$, the remainder is

If $\alpha$ and $\beta$ are the roots of $2x^2-3x-4=0$, then $\alpha^2+3\alpha\beta+\beta^2=$

$2x-3a-4>3x+5a+6$ is equivalent to

The sixth term and the eleventh term of an A.P. are $10$ and $30$ respectively. The first term is

If $2x=3y=5z$, then $x:y:z=$