`D( u pm v) = D(u) pm D(v)`

If |(x , 1),(1,x)| = |(2 , 0),(8,4)| then value of x is: (a) pm 3 (b) pm2 (c) pm4 (d) 0

If : sin A + cos A =1, "then" :sin A - cos A = A) pm 1 B)0 C) pm 2 D) pm 3

Calculate the percentage error in value of R is V= (50 pm 5)V " and "I= (5 pm 1)A .

The graph between object distance u and image distance v for a lens is given below. The focal length of the lens is. (a) 5 pm 0.1 (b) 5 pm 0.05 ( c) 0.5 pm 0.1 (d) 0.5 pm 0.05 . .

The circles x^2 + y^2 + 2ux + 2vy = 0 and x^2 + y^2 + 2u_1 x + 2v_1 y = 0 touch each other at (1, 1) if : (A) u + u_1 = v + v_1 (B) u + v = v_1 + u_1 (C) u/u_1 = v/v_1 (D) none of these

If f(x)=x+sinx ,g(x)=e^(-x),u=sqrt(c+1)-sqrt(c), v=sqrt(c) -sqrt(c-1),(c >1), then (a)fog(u) gof(v) (d) fog(u) > fog(v)

If u=f(x),v=g(x), then the value of D^*(udotv) is (D^*u)v+(D^*v)u b. u^2D^*v+v^2D^*u c. D^*u+D^*v d. u v D^*(u+v)