A binary operation on the real set of numbers excluding -...
A binary operation on the real set of numbers excluding -1 is such that for all m, n ∈ R, mΔn = m+n+mn. Find the identity element of the operation.
1
zero
-1/2
-1
Correct answer is B
mΔn = m+n+mn
Let e be the identity element
∴mΔe = eΔm = m
m+e+me = m
e+me = m-m
e+me = 0
e(1+m) = 0
e = 0 / (1+m)
e = 0
The positions of two countries P and Q are (15°N, 12°E) and (65°N, 12°E) respectively. What is t...
Find the value of x satisfying \(\frac{x}{2}\) - \(\frac{1}{3}\) < \(\frac{2x}{5}\) + \(\frac{1}{...
In the figure, find the area of XYZW ...
In this figure, PQRS is a parallelogram, PS = PT and < PST = 55\(^o\). The size of <PQR is...