3 years ago

Sin(a+b).cos(a-b) = sinacosa + sinbcosb

1 answer:

4 0

Sin (A + B) = sin A cos B + cos A Sin B
Cos (A - B) = cos A cos B + sin A sin B 

=> (SinACosB+ CosASinB) (CosACosB +SinASinB) 

=>SinACosACos^2B+Sin^2ACosBSinB+Cos^2A... 

=>SinACosA(Cos^2B+Sin^2B) +SinBCosB(Sin^2A+Cos^2A) 
we know that Sin^2+Cos^2=1 
=>SinACosA(1)+SinBCosB(1) 
=SinACosA+SinBCosB 
Proved

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Triangle ABC is an equilateral triangle with side AB, BC, and AC. If side BC is equal to 10 cm what is the measure of side AC?

nordsb [41]

Answer:

AC = 10 cm

Step-by-step explanation:

We are givne with a triangle ABC is an equilateral triangle with side AB, BC, and AC. We are given that side BC is equal to 10 cm . We are required to find the measurement of side AC.

The basic property of any equilateral triangle is that all the sides are equal. Hence

AB = BC = CA

BC=10 cm

Hence, AB = 10 cm and also AC=10 cm

7 0

3 years ago

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Airida [17]

Answer:

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