Question

prove that sin²A+cos²A=1

Answer 1

Hi Mate!!!

Take A as any angle

say A = 30°

Sin² ( 30 ) + Cos² ( 30 )

( 1 / 4 ) + 3 / 4

= 1

Answer 2

Answer:

Step-by-step explanation: In a triangle ABC , right angled at B

=AB square+BC square= AC square(1)

= Divide each term of eqn(1) by AC square

= AB square/AC sqaure+BC square/AC square = AC square/ AC square

= (Cos A) sqaure + (SinA) square=AC sqaure/AC square(Using applications of trignometry)

Cos square A + Sin square A = 1