16. If sin 3A = cos (A - 26%), where 3A is an acute angle, find 'A'.
Answers
Answer:
1. Find the common factos of the given terms:
(i) 12x, 36
(ii) 2y, 22xy
(iii) 14pq, 28p2q2
(iv) 2x, 3x2, 4
(v) 6abc, 24ab2, 12a2b
(vi) 16x3, –4x2, 32x
(vii) 10pq, 20qr, 30rp
(viii) 3x2y3, 10x3y2, 6x2y2z
Sol. (i) The numerical coefficient in the given monomials are 12 and 36.
The highest common factor of 12 and 36 is 12.
But there is no common literal appearing in the given monomials 12x and 36.
The highest common factor = 12.
(ii) 2y = 2 × y
22xy = 2 × 11× x × y
The comoon factors are 2, y
And, 2 × y = 2y
(iii) The numerical coefficients of the given monomials are 14 and 28.
The highest common factor of 14 and 28 is 14.
Answer:
Sin and cos and complimentary angles therefore,
Sin A = Cos ( 90 -A )
Sin 3A = Sin ( 90 - A - 26 )
Sin 3A = Sin ( 64 - A )
Cancelling the sin function,
3A = 64 - A
64 = 3A + A
64 = 4A
A = 64/4
A = 16