Post mathematic related questions here

[rst]

Average velocity= 72 km/h= 20m/s
Total time= 25s
Total distance= 20*25=500m

Let t1,t2,t3 be time for acceleration, uniform motion and retardation

Time for acceleration and retardation will be same

So t1 +t2+t1= 25
2 t1 + t2 = 25

Velocity after time t1
v1 = 0+5t1


Now we can draw v- t gragh of above motion which will be like trapezium

Distance= area of trapezium
500= 1/2 (t2+25)v1
1000= (25-2t1+25) 5t1
Solving t1=5

So t2=15s

 

[rst]

*imageshack.com/i/excBhjhYj

 

[powerhoney]

*imageshack.com/i/excBhjhYj

B. 4.5 cmxcm

 

[rst]

Yes answer is correct

 

[powerhoney]

Yes answer is correct

Posting the solution below!!!



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Yes answer is correct

Posting the solution below!!!




*i.imgur.com/GNIbbJd.jpg?1

 

[rst]

*imageshack.com/i/ip9OIBd7j

 

[powerhoney]

*imageshack.com/i/ip9OIBd7j

350 cmxcm

 

[rst]

Ans is correct

 

[rst]

*imageshack.com/i/p7bNY00cj

 

[ankush28]

Spoiler

*imageshack.com/i/p7bNY00cj

I don't know much about solving this with pen and paper but... I think it has something to with cyclic remainders, see the picture.
*i.imgur.com/TBChG1Q.png
And the answer is 18

 

[rst]

Ans is correct

Remainder is 18

 

[rst]

*imageshack.com/i/ex4gzsY2j

 

[rst]

Ans is option (c)

 

[rst]

Find the number of all possible selections of one or more questions from 10 given questions, each question having an alternative.

A)3^(10)

B) 2^ (10) -1

C) 3^(10) -1

D) 2^(10 )

 

[rst]

Ans is option (c) 3^10 -1

As for each question we have 3 options
1) do it 2) leave it 3) do alternative question

 

[rst]

*imageshack.com/i/pcWymDxgj

 

[rst]

Ans is A) y

 

[rst]

*imageshack.com/i/p58FCIDAj

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Option (B) is Cosα cosβ cosγ

 

[iittopper]

First expand all cos term . Then write the matrix in product form A*B . Then solve it normally .

 

[rst]

Ans is option (D) 0