WLA - Maths - Edexcel A Level - 1-A24Q

In binomial expansion, Pascal's triangle is used to calculate what for a term

• Position within the expansion

• Coefficient of the term

• Power of the term

• Value of the term

In the expansion of (a + b)ⁿ, the general term is given by:

• 
• 
• 
• 

The first few terms in a binomial expansion of the form (k + x)ⁿ where k is a constant can be used for calculating approximations if ...

• x is an integer

• x is small

• x is real

• x is large

Which one of these is valid?

•  $c=a^2+b^2-2ab\cos C$  

•  $\cos A\ =\ \frac{a^2+b^2-c^2}{2ab}$  

•  $\cos\ A\ =\ \frac{b^2+c^2-a^2}{2bc}$  

•  $c\ =\ \sqrt{a^2+b^2-2abCosC}$  

Why do we need to check for two possible triangles when one of the angles has the same sine value?

• The triangle may have been reflected.

• The angles must add up to 180 degrees.

• The triangle may have been rotated.

• Sine is periodic with a positive reflection 0-90 and 90-180.

Which one is true for all three trig functions?

• They have asymptotes.

• They pass through the origin.

• They have a periodicity of 360⁰.

• Within their periods, 50% of their values are positive and 50% are negative.

In the unit circle P(x,y) can be written as:

•  $\left(\sin\theta,\cos\theta\right)$  

•  $\left(\cos\theta,\sin\theta\right)$  

•  $\left(\sin\theta,\tan\theta\right)$  

•  $\left(\cos\theta,\tan\theta\right)$  

Solutions to $\tan\theta=p$  exist for:

• all values of p.

• between -1 and +1.

• between 0 and +1.

• between -1 and 0.

The principal value of a trigonometric function is:

• The y axis intercept.

• The angle returned for a ratio by a calculator.

• The first x axis intercept.

• The ratio returned for an angle by a calculator.

If  $\overrightarrow{AB}=\overrightarrow{CD}$  then which of these is NOT true about the two vectors?

• They are parallel.
  

• They are equal in length.

• They have the same gradient.

• They are colinear.