In a triangle ABC, prove that (a)`cos(A + B) + cos C = 0` (b)`tan( (A+B)/2)= cot(C/ 2)`
2,476 views · Published 12 October 2018 · 1:36 · Indexed 27 September 2026
Channel: Doubtnut · 2018 · Education
To ask Unlimited Maths doubts download Doubtnut from - https://goo.gl/9WZjCW In a triangle ABC, prove that (a)`cos(A + B) + cos C = 0` (b)`tan( (A+B)/2)= cot(C/ 2)`
More from this channel
-
2:28
IIT JEE LIMITS AND DERIVATIVES Evaluate:
`("lim")_(xrarr0)(sinx^0)/x`
-
4:29
IIT JEE LIMITS AND DERIVATIVES Evaluate the limit:
`("lim")_(xvecoo)((x+2)/(x+1))^(x+3)`
-
3:50
`A D` and `B E` are respectively altitudes of an isosceles triangle `A B C` with `A C=B C` . Pro...
-
4:19
IIT JEE PERMUTATIONS AND COMBINATIONS Find the number of distinct rational numbers `x`
such that ...
-
2:15
IIT JEE PERMUTATIONS AND COMBINATIONS Find the sum of the series `sum_(r=1)^n rxxr !dot`
-
2:47
JEE MAINS 2018 Find the points of local maxima and local minima,
if any, of each of the follo...
-
3:03
Find the number of polynomials of the form `x^3+a x^2+b x+c`
that are divisible by `x^2+1,w h e...
-
2:58
IIT JEE PERMUTATIONS AND COMBINATIONS Prove that `"^n C_r+^(n-1)C_r+...+^r C_r=^(n+1)C_(r+1)`
.