 If projections of three points A, B, C on a given plane are A′,B′,C′ ; then ΔA′B′C′=cosθ(ΔABC) , w

# Ask a Question

### Question Asked by a Student from EXXAMM.com Team

Q 1277134086.     If projections of three points A, B, C on a given plane are A′,B′,C′ ; then ΔA′B′C′=cosθ(ΔABC) , where θ is the angle between the planes ABC and ′B′C′ . In general, if A_0 is the area of any plane curve and A is the area of its projection on any plane, then A=cosθA_0

Suppose AB is a diameter of a circle and P is a plane through AB making an angle θ with the plane of the circle. If diameter of the circle is 2a, then the eccentricity of the curve of projection of the circle on P is A sin θ

B (2asinθ)/(1+a)

C (2acosθ)/(1+a)

D cos θ

#### HINT

(Provided By a Student and Checked/Corrected by EXXAMM.com Team)

#### Access free resources including

• 100% free video lectures with detailed notes and examples
• Previous Year Papers
• Mock Tests
• Practices question categorized in topics and 4 levels with detailed solutions
• Syllabus & Pattern Analysis