Marks
51-60
61-70
71-80
81-90
91- 100
Students
10
20
15
5
What do you mean by Range according to the stem?
Determine standard Deviation according the grouped data of the stem.
In light of the stem find out Mean Deviation.
2. mx2+nx+l=0,lx2+nx+m=0 \mathrm{mx}^{2}+\mathrm{nx}+l=0, l \mathrm{x}^{2}+\mathrm{nx}+\mathrm{m}=0 mx2+nx+l=0,lx2+nx+m=0.
Solve the equation 2x2+5x−9=0 2 x^{2}+5 x-9=0 2x2+5x−9=0 with the help of factor
There is a common root of the two equations in the stem, then show that m+l=±n \mathrm{m}+l= \pm \mathrm{n} m+l=±n.
If two roots of the 1st equation in the stem are α \alpha α and β \beta β then express the roots of the equation ml(x2+1)−(n2−2ml)x=0 as α and β. m l\left(x^{2}+1\right)-\left(n^{2}-2 m l\right) x=0 \text { as } \alpha \text { and } \beta \text {. } ml(x2+1)−(n2−2ml)x=0 as α and β.
3. A and B are two kinds of food containing protein and starch as per the following table:
Food
Protein (per kg)
Starch (per kg)
Price (per kg)
A
4
40 taka
B
6
3
50 taka
Daily minimum requirernent
16
11
What do you mean by linear programming?
Formulate a linear program for this problem.
Solve the linear program by graphically.
4. 16x2+25y2=400 16 x^{2}+25 y^{2}=400 16x2+25y2=400.
Taking the axes of the ellipse as the x x x and y y y axes, find the equation of the ellipse passing through the points (0,22) (0,2 \sqrt{2}) (0,22) and (−3,0) (-3,0) (−3,0)
Find out the vertexes, foci, eccentricity, length of its latus rectum.
Sketching the conic determine the equations of the lateral recta and equation of the directrices.
5.
To find the resultant and its direction of two forces 100 N 100 \mathrm{~N} 100 N and 70 N 70 \mathrm{~N} 70 N act at a point at an angle 62∘ 62^{\circ} 62∘.
When P P P is increased by (R+3) (\mathrm{R}+3) (R+3) and Q \mathrm{Q} Q is increased by (S+2) (\mathrm{S}+2) (S+2), the resultant again pass through the point C C C. Also when Q Q Q and (R+3) (R+3) (R+3) replaced by P P P and Q Q Q respectively the resultant passes through C \mathrm{C} C.
Then prove that R=S+(Q−R−3)2P−Q+1 \mathrm{R}=\mathrm{S}+\frac{(\mathrm{Q}-\mathrm{R}-3)^{2}}{\mathrm{P}-\mathrm{Q}}+1 R=S+P−Q(Q−R−3)2+1.
In the stem the two equal and opposite forces R \mathrm{R} R along any two parallel lines at a distance x x x apart in the same plane of P \mathrm{P} P and Q \mathrm{Q} Q. Then show that the resultant is displaced by a distance xRP+Q \frac{\mathrm{xR}}{\mathrm{P}+\mathrm{Q}} P+QxR.
[N. B. R=S+(Q−R−3)2P−Q+1 \mathrm{R}=\mathrm{S}+\frac{(\mathrm{Q}-\mathrm{R}-3)^{2}}{\mathrm{P}-\mathrm{Q}}+1 R=S+P−Q(Q−R−3)2+1 Replace
R=S+(Q−R−3)2P−Q−1 \mathrm{R}=\mathrm{S}+\frac{(\mathrm{Q}-\mathrm{R}-3)^{2}}{\mathrm{P}-\mathrm{Q}}-1 R=S+P−Q(Q−R−3)2−1]