Question

rs aggarwal class 10th = In a triangle ABC if angel B =90 degree and tan =1 then prove that 2 sin Acos A =1​

Answer 1

Step-by-step explanation:

it is not clear tan of which angle is 1

assuming TAN A=1

this means angle A is 45 degree

now sinA = sin 45 =

$1 \div \sqrt{2}$

cosA= cos 45 =

$1 \div \sqrt{2}$

now,

2 sinA cosA= 2*1/root 2* 1/root 2

= 2*1/2

=1

proved

Answer 2

Step-by-step explanation:

Step-by-step explanation:

it is not clear tan of which angle is 1

assuming TAN A=1

this means angle A is 45 degree

now sinA = sin 45 =

1 \div \sqrt{2}1÷2

cosA= cos 45 =

1 \div \sqrt{2}1÷2

now,

2 sinA cosA= 2*1/root 2* 1/root 2

= 2*1/2

=1

proved