: In ` A B Cdot` Show that, `tanA+tanB+tanC=tanAtanBtanC`

Column I Column II In A B C , if cos24+cos2B+cos2C=-1 then we can conclude that triangle is p. Equilateral triangle In A B C if tanA >0,tanB >0a n dtanAtanB 0,cotB >0a n dcotAcotB<1, then triangle is s. Obtuse angled triangle

If in a triangle ABC,tanA+tanB+tanC=6 and tanAtanB=2, then the triangle is acute angled triangle.

Each question has four choices a,b,c and d out of which only one is correct. Each question contains Statement 1 and Statement 2. Make your answer as: a) If both the statements are true and Statement 2 is the correct explanation of statement 1. b) If both the statements are True but Statement 2 is not the correct explanation of Statement 1. c) If Statement 1 is True and Statement 2 is False. d) If Statement 1 is False and Statement 2 is True. Statement 1: If A ,B ,C are the angles of a triangle such that angle A is obtuse, then tanBt a n C > 1. Statement 2: In any triangle, tanA=(tanB+tanC)/(tanBtanC-1)

If sec A - "cosec" A= "cosec" B - secB, "show that" tanA tan B = "tan"(A+B)/2

If a^2, b^2,c^2 are in A.P., then prove that tanA ,tanB ,tanC are in H.P.

If A + B = 45^@ , show that (1+tanA) (1+tanB) =2

If AleB show that A-B=phi

If A+B+C=pi, prove that (tanA)/(tanBdottanC)+(tanB)/(tanAdott a n C)+(tanC)/(tanAdottanB)=tanA+tanB+tanC-2cot A-2cot B-2cot C

In a A B C , if tanA:tanB :tanC=3:4:5, then the value of sinA sinB sinC is equal to (a) 2/(sqrt(5)) (b) (2sqrt(5))/7 (2sqrt(5))/9 (d) 2/(3sqrt(5))

If A cupB=B," show that, "A subeB.