please answer with steps
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Answers
Let the bus travel the distance x
Let the bus travel the distance x then, distance travelled by the man, before he would catch the bus=d+x
Let the bus travel the distance x then, distance travelled by the man, before he would catch the bus=d+xtime taken by man to catch the bus=(d+x)/u
for bus
distance travelled=x
acceleration=a
u=0
x=(1/2)×a×t^2
t^2=2x/a
t=√2x/√a
time taken by a man to get the bus=time in which bus covers a distance x
2x/a=(d+x)^2/u^2
2x/a=(d^2+x^2+2dx)/u^2
2xu^2=ad^2+ax^2+2adx
ax^2+2adx-2xu^2+ad^2=0
ax^2+(2ad-u^2)x+ad^2=0
for this equation to satisfy,,,
b^2-4ac should not equal to negative
b^2-4ac should not equal to negativeit can be 0 or greater than0
Now,here
b=2ad-u^2
c=ad^2
b^2-4ac=>(2ad-u^2)^2-4a^2d^2>=0
4a^2d^2+u^4-4adu^2-4a^2d^2>=0
u^4>=4adu^2
u^2/4a>=d
Hence option d) is the correct one
{hope it helps}