Hi all, my 3rd thread today (embarrassed)
I have an exercise that's really annoying me, it was given by an engineer friend of mine. Here it goes.
ABC is a triangle. a=BC b=AC c=AB p=semi-perimetre of the triangle
Al Kashi's formula is--> a2=b2+c2-2bc*cos(^A) "angle A"
1/a. Prove that 1+cos(^A)=[ 2p(p-a) ] / [bc]
b. Prove that 1-cos(^A)=[ 2(p-b)(p-c) ] / [bc]
2/ Deduce sin(A^) using a,b,c et p
3/ Demonstrate Heron's formula
Sqrt[ p(p-a)(p-b)(p-c) ] S=aire of ABC
4/ triangle T1 has sides that measure 16cm,17cm,18cm
triangle T2 has sides that measure 19cm,31cm,49cm
Which one has a bigger aire
MERCI a tout ceux qui m'aident, Mojito
my bad on Al Kashi's formula it should be:
a^2=b^2+c^2-2bc*cos(^A) "angle A"
I have an exercise that's really annoying me, it was given by an engineer friend of mine. Here it goes.
ABC is a triangle. a=BC b=AC c=AB p=semi-perimetre of the triangle
Al Kashi's formula is--> a2=b2+c2-2bc*cos(^A) "angle A"
1/a. Prove that 1+cos(^A)=[ 2p(p-a) ] / [bc]
b. Prove that 1-cos(^A)=[ 2(p-b)(p-c) ] / [bc]
2/ Deduce sin(A^) using a,b,c et p
3/ Demonstrate Heron's formula
Sqrt[ p(p-a)(p-b)(p-c) ] S=aire of ABC
4/ triangle T1 has sides that measure 16cm,17cm,18cm
triangle T2 has sides that measure 19cm,31cm,49cm
Which one has a bigger aire
MERCI a tout ceux qui m'aident, Mojito
my bad on Al Kashi's formula it should be:
a^2=b^2+c^2-2bc*cos(^A) "angle A"