Explanation

3cos2x - sinx = 0

cos 2A = 1 – 2 sin\(^2\)A

3(1 - 2sin\(^2\)x) - sinx = 0

3 - 6sin\(^2\)x -sinx = 0

let sinx = p

3 - 6p\(^2\) -p = 0

-6p2 - p +3 = 0

factors of p in the eqn:

p = 0.7953 or 0.6287

when p = 0.7953

p = sinx

x = sin\(^{-1}\) p

x = sin\(^{-1}\)(0.7953)

x = 52.68º

when p = 0.6287

p = sinx

x = sin\(^{-1}\) p

x = sin\(^{-1}\)(0.6287)

x = 38.95º

Correct Answer: A. the same number of valence electrons

Explanation

The correct answer is A. the same number of valence electrons.

• Groups are the vertical columns in the periodic table. Elements in the same group share the same number of valence electrons (electrons in their outermost shell), which gives them similar chemical properties.

• Elements in the same *period* (horizontal row) have the same number of electron shells.

• Atomic size increases as you move down a group, so elements in the same group do not have the same atomic size.

Correct Answer: C. is an intimate form of expression

Correct Answer: C. found in the very act

Correct Answer: B. eliminate all opposition to their presence in the hinterland

Correct Answer: C. \((R \cap P) \subset (R \cap U)\)

Explanation

All the statements are false except option C.

\(R \cap P = {3, 5, 7} and R \cap U = {2, 3, 5, 7, 11}\)

\(\therefore (R \cap P) \subset (R \cap U)\)

Explanation

(a) Thrift societies; are associations established to encourage savings among members . Members are made to contribute money at regular intervals (e.g monthly) out of which loans are granted to members who are in need of finance. It is formed by low income earners. Interests charged on loans are usually low as compared to that charged on bank loans.

(b) Services rendered by thrift societies to their members are:

(i) The thrift societies grant loans to members at low interest rates with no requirement for a collateral.

(ii) Members are encouraged to save a little of their income.

(iii) A member of a co-operative thrift society can obtain money to buy items which he would have otherwise been unable to afford.

(iv) The society can act as guarantors to their members who may involve in hire purchase.

(v) They encourage inter-personal relationship through the brotherly and friendly relationship that exist among their members.

Correct Answer: B. Histone acetylation

Explanation

Histone acetylation is the process of adding acetyl groups to positively charged lysine groups of histones. This process loosens the histone which allows for an easier initiation of transcription, which will lead to greater gene expression. DNA methylation does the opposite by adding methyl groups to DNA and lowering the rate of transcription. Alternative RNA splicing deals with RNA having certain introns and exons spliced out in a manner that produces different strands of mRNA from the same template strand of RNA. Addition of 5

Correct Answer: B. Magnesium chloride

Explanation

Magnesium chloride is used in antacid medications to relieve heartburn and indigestion. It helps neutralize excess stomach acid.

Correct Answer: A) PH3 CO and CO2