C-16-Q035mediumsingle_mcq

Two roads make an angle $120°$ at a place. Two persons walk for $5$ hours at $10$ km/h and $8$ km/h respectively. The direct distance between them squared (in km²) is —

a $4900$
b $6100$
c $1200$
d $4000$

ব্যাখ্যা

The distances are $50$ km and $40$ km, with included angle $120°$ . By the law of cosines, $d^2=50^2+40^2-2(50)(40)\cos120°=4100+2000=6100$ .

এই অধ্যায়ের আরও প্রশ্ন

C-16-Q036Approximate direct distance between the two persons in the previous problem is —
C-16-Q037In right-angled triangle with right angle at , , . Then equals —
C-16-Q038With , , and , the length equals —
C-16-Q039In the same triangle, equals —
C-16-Q040The ratio of areas in the above figure is —
C-16-Q041The hypotenuse of a right triangle is m and one side is of the other. The two sides are —
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C-16-Q044The semi-perimeter of a triangle with sides cm is —
C-16-Q045Equal sides of an isosceles triangle are m, area sq m. Two possible values of the base (m) are —

Chapter 16: Mensuration — সব প্রশ্ন দেখুন (210টি) →

Two roads make an angle $120°$ at a place. Two persons walk for $5$ hours at $10$ km/h and $8$ km/h respectively. The direct distance between them squared (in km²) is —

4900

6100

1200

4000

ব্যাখ্যা

The distances are $50$ km and $40$ km, with included angle $120°$ . By the law of cosines, $d^2=50^2+40^2-2(50)(40)\cos120°=4100+2000=6100$ .

Two roads make an angle 120°120°120° at a place. Two persons walk for 555 hours at 101010 km/h and 888 km/h respectively. The direct distance between them squared (in km²) is —

ব্যাখ্যা

এই অধ্যায়ের আরও প্রশ্ন

Two roads make an angle 120°120°120° at a place. Two persons walk for 555 hours at 101010 km/h and 888 km/h respectively. The direct distance between them squared (in km²) is —

ব্যাখ্যা

এই অধ্যায়ের আরও প্রশ্ন

Two roads make an angle $120°$ at a place. Two persons walk for $5$ hours at $10$ km/h and $8$ km/h respectively. The direct distance between them squared (in km²) is —

Two roads make an angle $120°$ at a place. Two persons walk for $5$ hours at $10$ km/h and $8$ km/h respectively. The direct distance between them squared (in km²) is —