PreCalculus 1st Semester Review (solutions)...PreCalculus 1st Semester Review (solutions) Author...
Transcript of PreCalculus 1st Semester Review (solutions)...PreCalculus 1st Semester Review (solutions) Author...
Precalculus First Semester Review
18) Use change of base to approximate the following to three decimal places 𝑎) log! 216 𝑏) log! 91 𝐥𝐨𝐠𝟐𝟏𝟔 𝐥𝐨𝐠𝟖
= 𝟐.𝟓𝟖𝟓 𝐥𝐨𝐠𝟗𝟏𝐥𝐨𝐠𝟐
= 𝟔.𝟓𝟎𝟖 19) Evaluate the following limits 𝑎) lim!→!
!!!!!!!"!!!
𝑏) lim!→!! !!! !!! !!!!
!
𝑐) lim!→!
!!!! !!
𝑑) lim!→!!!
!!!!!!!
20) A certain population (in thousands) grows according to the equation 𝑃 = 40𝑒!.!"#!
where P represents the population and t represent the number of years since 2000. a) Determine the year when the population 60 thousand will be reached. 𝟔𝟎 = 𝟒𝟎𝒆𝟎.𝟎𝟐𝟓𝒕 𝟏.𝟓 = 𝒆𝟎.𝟎𝟐𝟓𝒕 𝐥𝐧 𝟏.𝟓 = 𝟎.𝟎𝟐𝟓𝒕 𝒕 = 𝐥𝐧 𝟏.𝟓
𝟎.𝟎𝟐𝟓= 𝟏𝟔.𝟐𝟏𝟗 𝒚𝒆𝒂𝒓𝒔
𝟐𝟎𝟏𝟕 b) Determine the population in 2003 𝑷 𝟑 = 𝟒𝟎𝒆𝟎.𝟎𝟐𝟓(𝟑) = 𝟒𝟎.𝟏𝟏𝟓 𝒐𝒓 𝟒𝟏,𝟏𝟏𝟓 c) Determine the initial population. 𝟒𝟎,𝟎𝟎𝟎 21) Given 𝐴 = 1 0
3 4 and 𝐵 =−3 20 3
a) Find 3𝐴 + 𝐵 b) Find AB d) Find 𝐴!! 22) Given the geometric sequence with 𝑎! = 32 and 𝑟 = !
!
a) Write the formula 𝑎! for the sequence
𝒂𝒏 = 𝟑𝟐 𝟏𝟐
𝒏!𝟏
b) Write the first five terms of the sequence 𝟑𝟐,𝟏𝟔,𝟖,𝟒,𝟐 c) Determine the term 𝑎!"
𝒂𝟏𝟐 = 𝟑𝟐 𝟏𝟐
𝟏𝟐!𝟏= 𝟏
𝟑𝟐
Precalculus First Semester Review
23) Given the arithmetic sequence with 𝑎! = 20 and 𝑑 = −3 a) Write the formula 𝑎! for the sequence 𝒂𝒏 = −𝟑𝒏+ 𝟐𝟑 b) Write the first four terms of the sequence 𝟐𝟎,𝟏𝟕,𝟏𝟒,𝟏𝟏 c) Determine the term 𝑎!" 𝒂𝟏𝟎 = −𝟑 𝟏𝟎 + 𝟐𝟑 = −𝟕 24) Determine the value of the account with an initial balance of $3000 that is compounded quarterly with an interest rate of 8% after 5 years.
𝑨 = 𝟑𝟎𝟎𝟎 𝟏+ .𝟎𝟖𝟒
𝟒 𝟓= 𝟒𝟒𝟓𝟕.𝟖𝟒
25) Determine the value of an account with an initial balance of $3000 that is compounded continuously with an interest rate of 8% after 5 years. 𝑨 = 𝟑𝟎𝟎𝟎𝒆.𝟎𝟖(𝟓) = 𝟒𝟒𝟕𝟓.𝟒𝟕 26) Determine the coefficient of the following terms in the expansion of 3𝑥 + 6𝑦 ! a) 𝑥!𝑦! b) 𝑥!𝑦 𝟗𝟕𝟐𝟎 𝟐𝟒𝟑𝟎 27) Evaluate the following a) 𝐶! ! b) 𝐶! ! c) 𝐶! ! 28) Write in a + bi form: !!!!
!!!!
𝟐!𝟒𝒊𝟑!𝟐𝒊
𝟑!𝟐𝒊𝟑!𝟐𝒊
= 𝟔!𝟒𝒊!𝟏𝟐𝒊!𝟖𝒊𝟐
𝟗!𝟒𝒊𝟐= 𝟔!𝟏𝟔𝒊!𝟖
𝟗!𝟒= !𝟐!𝟏𝟔𝒊
𝟏𝟑= − 𝟐
𝟏𝟑+ 𝟏𝟔𝒊
𝟏𝟑
29) Graph the function and tell whether or not it has a point of discontinuity at x = 0. If there is a discontinuity, tell whether it is removable or non-‐removable. a) 𝑓 𝑥 = !
! b) 𝑔 𝑥 = !!!!
!
non-‐removable removable
Precalculus First Semester Review
30) Simplify a) log!! 11! b) ln !
! c) log!
!!"
𝟒 −𝟏 −𝟑 31) Find the zeros of the function algebraically. a) 𝑓 𝑥 = 3𝑥! + 2𝑥 − 5 b) 𝑓 𝑥 = 𝑥! − 36𝑥 𝟑𝒙𝟐 + 𝟐𝒙− 𝟓 = 𝟎 𝒙𝟑 − 𝟑𝟔𝒙 = 𝟎 𝟑𝒙+ 𝟓 𝒙− 𝟏 = 𝟎 𝒙 𝒙𝟐 − 𝟑𝟔 = 𝟎 𝒙 = − 𝟓
𝟑,𝟏 𝒙 𝒙− 𝟔 𝒙+ 𝟔 = 𝟎
𝒙 = 𝟎,−𝟔,𝟔 32) Determine whether the functions are even, odd, or neither a) 𝑓 𝑥 = 3𝑥! − 2𝑥 b) 𝑔 𝑥 = 2𝑥! − 3𝑥! + 5 ODD EVEN 33) Do the following functions have an inverse? If so, find it a) 𝑓 𝑥 = 𝑥! + 1! b) 𝑦 = 2 − 𝑥 𝒙 = 𝒚𝟐 + 𝟏𝟑 𝒙 = 𝟐− 𝒚 𝒙𝟑 = 𝒚𝟐 + 𝟏 𝒙𝟐 = 𝟐− 𝒚 𝒙𝟑 − 𝟏 = 𝒚𝟐 𝒚 = 𝟐− 𝒙𝟐 𝒚 = 𝒙𝟑 − 𝟏 34) Divide !
!!!!!!!!
with long division 35) Divide !!!!!!!!!!!!
with synthetic 𝒙𝟐 + 𝟐𝒙+ 𝟑 𝟓𝒙𝟑 − 𝟓𝒙𝟐 + 𝟑𝒙− 𝟑− 𝟏
𝒙!𝟏
36) Where is the following function discontinuous? a) 𝑦 = !!!
!!! b) 𝑦 = !
!!!!!!!
𝒙 = 𝟑 𝒙 = −𝟏,−𝟑