Conditional Identities

IMPORTANT

Conditional Identities: Overview

This topic covers concepts such as Trigonometric Identities and Inequalities Based on Triangles, Conditional Identities Based on Triangles, and Trigonometric Inequalities Based on Triangle.

Important Questions on Conditional Identities

HARD
IMPORTANT

If in a ABC, tanA+tanB+tanC>0, then the triangle is

MEDIUM
IMPORTANT

If A+B+C=π,nZ, then tannA+tannB+tannC is equal to

MEDIUM
IMPORTANT

In any triangle ABC, which is not right angled  Σ  cos  cosec  cosec  C   is equal to

EASY
IMPORTANT

If α, β, γ are real numbers satisfying α+β+γ=π, the minimum value of the given expression sinα+sinβ+sinγ is

MEDIUM
IMPORTANT

If A+B+C=π, then prove that tanA+tanB+tanC=tanA.tanB.tanC.

HARD
IMPORTANT

If  A, B, C are angles of ABC and  tanAtanC=3, tanBtanC=6, then 

HARD
IMPORTANT

If ABC is a triangle and tanA2, tanB2, tanC2 are in H.P., then the minimum value of cotB2 is equal to

MEDIUM
IMPORTANT

If sin-1a+sin-1b+sin-1c=π , then the value of a 1-a2+b1-b2+c1-c2 will be

MEDIUM
IMPORTANT

In a triangle ABC, cotA + cotB + cotC = cotθ .

sinAsinBsinC1+cosAcosBcosC=

HARD
IMPORTANT

In a triangle ABC, if cotA + cotB + cotC = cotθ, then the possible value of θ  is-

HARD
IMPORTANT

If x+y+z=xyz , then the value of x1-y2 1-z2+y1-x21-z2+z1-x21-y2 is

HARD
IMPORTANT

Statement - 1: The minimum value of the expression sinα+sinβ+sinγ where α, β, γ are real numbers such that α+β+γ=π , is not – 3 

Statement - 2: α, β, γ are angles of a triangle

HARD
IMPORTANT

  Column – I   Column – II
A. In an acute angled triangle ABC, the least values of secA and tan2A are λ and μ respectively, then p. λ+μ=2
B. In a triangle ABC, the least values of cosecA2 and sec2A2 are λ and μ respectively, then q. μ-λ=3
C. In a triangle ABC, the least values of cosecA2 and cosec2A are λ and μ respectively, then r. λ-μ=4
    s. 3λ-2μ=0
    t. 2λ-3μ=2

HARD
IMPORTANT

In a ΔABC, if cosAcosBcosC=3-18 and sinA.sinB.sinC=3+ 38 , then on the basis of above information, answer the following questions:

The value of tanA+tanB+tanC is:

The angles of ΔABC are :

HARD
IMPORTANT

In a ΔABC, if cosAcosBcosC=3-18 and sinA.sinB.sinC=3+ 38 , then on the basis of above information, answer the following questions:

The value of tanA+tanB+tanC is:

EASY
IMPORTANT

In a triangle ABC, if a = 7, b = 8, c = 9, then the length of the line joining B to the midpoint of AC is

MEDIUM
IMPORTANT

If tanA:tanB:tanC=1:2:3A+B+C=π, then sinA:sinB:sinC is equal to

EASY
IMPORTANT

The angular elevation of a tower CD at a point A due south of it is 60°, and at a point B due west of A, the elevation is 30°. If AB=3 km, the height of the tower is:

EASY
IMPORTANT

If in ΔABCtanA+tanB+tanC=x2+6x+5, then set of values of x for which ΔABC is obtuse angled,

HARD
IMPORTANT

If A+B+C=π and cosAcosecBcosecC=k, then k is equal to