有一对渐开线标准直齿圆柱齿轮啮合,已知z1=19,z2=42,m=5mm.(1)试求当a'=20°时,这对齿轮的实际啮合线B1B2的长、作用弧、作用角及重合度εa;(2)绘出一对齿和两对齿的啮合图,并按图上尺寸计算重合度.
已知类Myst有一个只需要一个double型参数的构造函数,且将运算符“-”重载为友元函数。要使语句序列 Myst x(3.2),y(5.5),z(0.0); z=8.9-y; y=x-6.3; 能够正常运行,运算符函数operator-应该在类中声明为
A.friend Myst operator-(Myst&,Myst&);
B.friend Myst operator-(Myst,Myst);
C.friend Myst operator-(Myst,Myst&);
D.friend Myst operator-(Myst&,Myst);
A.friend Myst operator-(Myst&,Myst&);
B.friend Myst operator-(Myst,Myst);
C.friend Myst operator-(Myst,Myst&);
D.friend Myst operator-(Myst&,Myst);
已知X=93H,Y=D6H,Z=EAH,则(X).Z=(11)。
A.BAH
B.90H
C.AAH
D.94H
已知X=8,Y=5,Z=27,表达式X^2/5+6*Y-7*2+(4+Z/7)^2的值为
A.26.8
B.45.8
C.44.8
D.92.8
A.-127
B.125
C.-125
D.1
A.kk>='A'&& kk<='Z'
B.!(kk>='A'‖kk<='Z')
C.(kk+32)>='a'&&(kk+32)<='z'
D.isalpha(kk)&&(kk<91)
已知X=8,Y:5,Z=28,表达式X~2/5+6*Y-7*2+(4+Z/7)~2的值为
A.26.8
B.45.8
C.44.8
D.92.8
A.kk>='A'&&kk<='Z'
B.!(kk>='A'||kk<='Z')
C.(kk+32)>='a'&&(kk+32)<='z'
D.isalpha(kk)&&(kk<91)
A.kk>=′A′&& kk<=′Z′
B.!(kk>=′A′||kk<=′Z′)
C.(kk+32)>=′a′&&(kk+32)<=′Z′
D.isalpha(kk)&&(kk<91)