3-d

Related Questions

• If the co-ordinates of the points $A,B,C,D$ be (2, 3, –1), (3, 5, – 3), (1, 2, 3) and (3, 5, 7) respectively, then the projection of $AB$ on $CD$ is

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• Let (3, 4, –1) and (–1, 2, 3) are the end points of a diameter of sphere. Then the radius of the sphere is equal to

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• If a line makes angles $\alpha ,\beta ,\gamma ,\delta $ with four diagonals of a cube, then the value of ${{\sin }^{2}}\alpha +{{\sin }^{2}}\beta +$ ${{\sin }^{2}}\gamma +{{\sin }^{2}}\delta $ is

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• Under what condition does a straight line $\frac{x-{{x}_{0}}}{l}=$$\frac{y-{{y}_{0}}}{m}=\frac{z-{{z}_{0}}}{n}$ is parallel to the xy-plane

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• The angle between the lines whose direction cosines satisfy the equations $l+m+n=0$, ${{l}^{2}}+{{m}^{2}}-{{n}^{2}}=0$ is given by

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