Question

In right triangle abc, bc = 7 cm, ac - ab = 1 cm and  b = 90º. then the value of cos a + cos b + cos c is:

Answer 1

Here AB = 24 CM AND AC= 25 CM
cosA + cosB + cosC = 38/25

Answer 2

Answer:

Step-by-step explanation:

Given: BC= 7 cm

AC-AB= 1 cm

Sol: Let AB=x

∴ AC=x+1

From Pythagoras theorem,

x²+7²=(x+1)²

x²+49=x²+1+2x

2x=49-1=48

∴x=24

AB=24

AC=x+1=24+1=25

Cos A =24/25

Cos B= 7/25

Cos C= 7/25

Cos A+Cos B+Cos C=24/25+7/25+7/25

=38/25