if A + B =225
prove that
(cotA.cotB)/[(1 + cotA)(1 + cotB)] = 1/2
if A + B =225
prove that
(cotA.cotB)/[(1 + cotA)(1 + cotB)] = 1/2
paradox xyz cool , 15 Years ago
Grade 11
Trigonometry> plz plz plz helpppppp...
2 Answers
vikas askiitian expert
(COTACOTB)/[(1+COTA)(1+COTB)] = 1/2
TAKING LHS
= (COTACOTB)/[1+COTACOTB +COTA+COTB] ...................1
NOW
COT(A+B)=COTACOTB - 1/COTA+COTB
A+B = 225 (GIVEN)
SO
COT225 = COTACOTB - 1/COTA+COTB
1 = COTACOTB-1/COTA+COTB (COT225=1)
COTA + COTB =COTACOTB - 1 ......................2
PUTTING 2 IN 1 WE GET
LHS= COTACOTB/2COTACOTB
=1/2 = RHS
HENCE PROVED
sumanth
(COTACOTB)/[(1+COTA)(1+COTB)] = 1/2
TAKING LHS
= (COTACOTB)/[1+COTACOTB +COTA+COTB] ...................1
NOW
COT(A+B)=COTACOTB - 1/COTA+COTB
A+B = 225 (GIVEN)
SO
COT225 = COTACOTB - 1/COTA+COTB
1 = COTACOTB-1/COTA+COTB (COT225=1)
COTA + COTB =COTACOTB - 1 ......................2
PUTTING 2 IN 1 WE GET
LHS= COTACOTB/2COTACOTB
=1/2 = RHS
HENCE PROVED
LIVE ONLINE CLASSES
Prepraring for the competition made easy just by live online class.
Full Live Access
Study Material
Live Doubts Solving
Daily Class Assignments
Other Related Questions on trigonometry
In ABC, if cot A+cot B+cot C = cosecA cosecB cosecC, then prove that ABC is right angle triangle.
In ABC, if cot A+cot B+cot C = cosecA cosecB cosecC, then prove that ABC is right angle triangle.
trigonometry
1 Answer Available
Last Activity: 3 Years ago
- Find the general solution of equation tan3∂=cot2∂
For all angles between -720 and +720
- Find the general solution of equation tan3∂=cot2∂
For all angles between -720 and +720
trigonometry
1 Answer Available
Last Activity: 3 Years ago
To prove : Cosec(45 degree - A)Cosec(45 degree + A) = 2SecA
To prove : Cosec(45 degree - A)Cosec(45 degree + A) = 2SecA
trigonometry
1 Answer Available
Last Activity: 3 Years ago
Derive a formula for the area of the triangle, given b, A, B, and C. That is, derive the formula: (b^2sinAsinC)/(2sinB)
Derive a formula for the area of the triangle, given b, A, B, and C. That is, derive the formula: (b^2sinAsinC)/(2sinB)
trigonometry
1 Answer Available
Last Activity: 4 Years ago
WHAT IS THE LIMIT WHEN X TOWARDS TO 0 OF sin6x/5x ? lim𝑥→0 𝑠𝑖𝑛6𝑥/5𝑥
WHAT IS THE LIMIT WHEN X TOWARDS TO 0 OF sin6x/5x ? lim𝑥→0 𝑠𝑖𝑛6𝑥/5𝑥
trigonometry
1 Answer Available
Last Activity: 4 Years ago