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析(3x²+x-2)/(x-2)²(1-2x)为部分分式.
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求圆锥曲线 x² +y² = 49 及 x² +y² - 20y +90 =0之公切线的长.
求圆锥曲线 2x²-8xy - 4y² - 4y +1=0 之焦点及准线.
某人在高处望见正东海面上一船首，其俯角为 30°，当船向正南行 a 里后，求得船首俯角为 15°，问此人之视点高出海面若干?
设一四面体有一三面角与另一四面体的一三面角对称，求证：其体积之比等于此两三面角三棱分别的乘积之比.
Find the locus of point which moves so that the sum of its distance from the points (-7, 4) and (9, 4) is always 20 units. Determine the center, foci, vertices,axis and eccentricity. Locate all points.
Show that the tangents to the parabola y² = 4px at the extremities of the latus return are perpendicular and meet at the intersection of the directrix with a-axis.
Show that the tangent to a hyperbola makes equal angles with the focal radii drawn to the point of tangency.
Find the distance from the point (-1, -4) to the straight line which is drawn through (-2,6) and the perpendicular to the line joining (3,6) and (-5,-1).
Two towers, A and B, on the shore of a lake can be observed from only one point C on the opposite shore. The lines joining the bases of two towers subtend anangle of 63°42' at C. The heights of the towers are 132 feet and 89 feet, and the angle of elevation of the tops as seen from C are 8°13' and 7°21' respectively.Find the distance AB.
The sides of a triangle are 149,163 and 222. To find(1) The area of the triangle.(2) The radius of the inscribed circle.(3) The angles of the triangle.
如果n是正整数，那么1/8[1-(-1)n](n2-1)的值【 】
已知正整数n,恰有36个不同的质数整除n，对k=1,2,3,4,5，记[(k-1)n/5,kn/5]中互质的整数个数为Cn，已知C1,C2,C3,C4,C5不完全相同.求证：(Ci - Cj)2 ≥236.
安徽省代数式
分解因式：a2-2ab+b2-6a+6b+5.
分解因式x2y - 2y3.
试分 ab(x²- y²)+ xy (a²-b²)为因数.
北京师范大学代数式
试将下列繁分数简单之：
有人定酒二坛，两坛所盛斤数不等，原定一盛甲酒每斤8角，一盛乙酒每斤5角.今误将甲坛盛乙酒，乙坛盛甲酒，酒商要求加洋一元五角.问两坛斤数各几何?
若a:b=c:d，试证(a2+b2):a3/(a+b)=(c2+d2):c3/(c+d).
化简((x2-y2)(2x2-2xy))/4(x-y)2-xy/(x+y)
设x+y+z =0,证明: x³ +y³ +z³ = 3xyz
试求适合5x+3y>121,7/4 x+y=42 二式之x,y之值之界限.
劈生数(因式分解)：3a²+a-6a²b-2b
劈生数(因式分解)：(2x+3y)²-(x-4y)²
劈生数(因式分解)：a4+a²b²+b4
解明：(6x+5)/(8x-15)-(1+8x)/15=(1-x)/3+(3-x)/5
(x+y)6=______
x4+4之有理因子为____________.
