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1.Vector ac=(-2,-2,1), vector bc=(-1,1,0), the product of vector ac and vector bc = (-2)*(1)+(2)*1+1*0=0, so ac bc
2.Vector ab=(-1,-3,1), let the vector ah=tab, we get h(1 (1+t),(2-t) (1+t),t (1+t)), vector ch=((2+t) (1+t), (2-t) (1+t),-1 (1+t)), ch 丄ab gets ch*ab=0 to get t=9 2, substitution can get h
3.m is obtained by using the midpoint formula, and then t is obtained by using the line segment fixed score point formula, and the coordinates of t are the average of the coordinates of a, b, and c.
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1.The square of the line segment ab = z ab + (|xa|+|xb|)²ya|+|yb|Here the lowercase letter is the x, y, z, and distinction sign that distinguishes the two points of ab.
Substituting the two-point coefficient of ab into the solution yields: ab = 11Again, the above formula is used to solve: ac=3, bc=2
Derived from the Pythagorean theorem: abc is a right triangle, and c=90° is used for reasoning, and it can be obtained by reverse deduction.
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Solution: Let form a straight line x=1, from 2x-y=0: y=2, from 3x-2y+z=1 to get :z=2;
Let x=0, get: y=0, z=1; Straight lines pass through points (1,2,2) and points (0,0,1).
The vector composed of the crossing point (-2,3,1) and the crossing point (1,2,2) is v1=; The vector formed with the crossing point (0,0,1) is v2=, and the normal vector n=v1xv2=x=
The plane equation between the crossing point (-2, 3, 2) and the straight line l is: 3(x+2)+2(y-3)-6(z-1)=0, that is, 3x+2y-6z+6=0.
Answer: 3x+2y-6z+6=0.
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Let a and b be the two moving points on the plane oxz and oyz, respectively, and satisfy the vectors oa*ob=1. Find the trajectory equation for the midpoint of AB.
Solution: Let the midpoint of ab be m(x,y,z), then a(2x,0,z1),b(0,2y,2z-z1), and the vector oa*ob=1 yields z1(2z-z1)=1
Please check the question.
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The plane 2x+y+kz-1=0 is the general equation of the plane with the normal vector n=(2, 1, k).
The straight line (x-4) 3=(y+3) 4=z (-2) is a point-oriented equation with the direction vector s=(3, 4, -2).
If the line is parallel to the plane, the normal vector of the plane is perpendicular to the direction vector of the line.
That is, the product of the quantity of the two vectors is 0. That is, 2*3+1*4-2k=0 gives k=5
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This problem can be solved by knowing that df(u,v)dudv=p is a fixed-value problem. >>>More
Ask about power, why is the answer v?
But to your problem, you delete the 2l on both sides of the formula, that is, a=gsin The acceleration here is to decompose gravity, specifically to establish a Cartesian coordinate system along the inclined plane direction, because the inclined plane is smooth, the object only has gravity and elastic force (elastic force is the supporting force of the inclined plane to the object), in this, the elastic direction has no velocity, so the acceleration of the object is all provided by the component of gravity in the inclined plane direction. >>>More
Solution: (1) Because p=w t w=fs
So p=fv >>>More
Solution: The straight lines a and b of different planes are at an angle of 80 degrees, you may wish to make parallel lines of two straight lines of different planes at the same time through the point p, at this time, the angle of the two straight lines is the angle formed by the coplanar straight line, and the original problem becomes the intersection point p of the two coplanar straight lines, and there are only 2 straight lines equal to the angles formed by these two coplanar straight lines, you may wish to set the equal angle as x >>>More
a={x|0,-4}
If a intersects b=b, b={x|0, -4} or b={x|0} or b={x|-4} >>>More