Question

don't put irrelevant answers​

Answer 1

Answer:

L.H.S. = tan 10˚ tan 15˚ tan 75˚ tan 80˚

= tan 10˚ tan 15˚ tan (90˚ – 15˚) tan(90˚ – 10˚)

= tan 10˚ tan 15˚ cot 15˚ cot 10˚

1/cot10˚ × 1/cot 15˚ × cot 15˚ × cot 10˚

= 1 = R.H.S.

Hence proved.

(ii) L.H.S. = cos 1˚ cos 2˚ cos 3˚ …..cos 180˚

= cos1˚ cos2˚ cos 3˚ …..cos 89˚ cos 90˚ ….cos 180˚

= cos 1˚ cos 2˚ cos 3˚ ….cos 89˚ × 0 × cos 91˚ ….cos 180˚

= 0 = R.H.S.

Answer 2

Step-by-step explanation:

(b)x3-3x2-x+3

=x^2(x+3)+1(x+3)

=(x^2+1)(x+3)

(c)AB is the chord of circle with centre O and radius OA

OM is perpendicular to AB

Therefore, AB=48cm

OA=25cm

OM⊥AB

M is the mid-point of AB

AM = 1/2 AB = 1/2×48=24cm

Now right △OAM,

OA

2

=OM

2

+AM

2

(by Pythagoras Axiom)

(25)

2

=OM

2

+(24)

2

OM

2

=(25)

2

−(24)

2

=625−576

=49=(7)

2

OM=7cm

This is the right answers for your question.