D.G KHAN MATH 2012 PART-I
(OBJECTIVE) Marks:20
NOTE: You have four choices for each objective type question as A , B C and D . The choice which you think is correct; fill that circle in front of that question number. Use marker or pen to fill the circles. Cutting or filling two or more circles will result in zero mark in that question. Attempt as many questions as given in objective type question paper and leave others blank. Write the letter A, B, C or D in the column (Write coma option) against each question. If there is a contradiction in the bubble and band written answer, bubble option will be considered correct
QUESTION NO (1)
(A) Closure law
(B) Commutative law
(C) Associative law
(D) Distributive Law
MATHEMATICS TIME: 2.30 HOURS
SUBJECTIVE MARKS : 80
SECTION-I
QUESTION NO. 3 Attempt any eight (8) short questions 16
QUESTION NO, 4 Attempt any Nine (9) short questions 18
SECTION-II Note: Attempt any three questions from this section
5.(a) If (G,* ) is a group , then prove that
(i) Identity element is unique (ii) Inverse of each element is unique
(b) If A= then prove that.
(i) If A+ is skew Hermitian (ii) A-
is Hermitian
6.(a) Show that roots of x2 + (mx +c)2 = a2 will be equal if c2= a2 (1+m2 )
(b) Which term of the sequence x2-y2,x+y, ,……… is
=?
7.(a) A die is thrown , find the probability that the dots on the top are Prime Numbers or Odd Numbers
(b) Find the co-efficient of xn in the expansion of
8. (a) Prove that Si + Co
(b) lf α β, ϒ, are angle of a triangle ABC.
Show that Cot +Cot
+Cot
= Cot
Cot
Cot
9. (a) Prove that +
+
+
=
(b) Prove that tan-1 + tan-1
= tan-1
+tan-1