Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-db.php on line 556 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/util/string.php on line 702 Deprecated: substr(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/pages/question.php on line 185 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/pages/question.php on line 198 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/app/users.php on line 1277 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/util/string.php on line 702 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/util/string.php on line 702 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/pages/question-view.php on line 473 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/util/string.php on line 702 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/util/string.php on line 702 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-base.php on line 722 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-base.php on line 722 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-base.php on line 722 2016 Test 1 Q1 - Actuarial Science Hotseat
Welcome to the hotseat. We've prepared a guide if you'd like to read more about how it works.
  • Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 648 Q&A Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 661
  • Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 648 Questions Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 661
  • Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 648 Unanswered Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 661
  • Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 648 Categories Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 661
  • Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 648 Users Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 661
  • Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 648 Ask a Question Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 661
0 votes
152 views
Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 160 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 162 in BUS 3024S - Contingencies by (1.7k points)

Hi, could you pleas explain how the (1-y)^-2 is obtained in the solution below. image

Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 935 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 935

1 Answer

+1 vote
Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 160 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 162 by (670 points)
Hi

Please see the last line you attached in the second image. If you differentiate sum (y^k) you will get sum (k*y^k-1). 

So sum (k*y^k-1) = first derivative of sum (y^k) = first derivative of (1-y)^-1 = - (1-y)^-2 *(-1)= (1-y) ^-2
Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 935 Deprecated: strlen(): Passing null to parameter #1 ($string) of type string is deprecated in /usr/www/users/acscidewug/qa-include/qa-theme-base.php on line 935
Welcome to Actuarial Science hotseat, where you can ask questions and receive answers from other members of the community.

Click here for our guide to using the hotseat.

Categories

...