Checking if AP or not and finding a, d
Checking if AP or not and finding a, d
Last updated at April 16, 2024 by Teachoo
Ex 5.1, 2 Write first four terms of the A.P. when the first term a and the common difference d are given as follows (i) a = 10, d = 10 First term = a = 10 Common difference = d = 10 Second term = First term + Common difference = 10 + 10 = 20 Third term = Second term + Common difference = 20 + 10 = 30 Fourth term = Third term + Common difference = 30 + 10 = 40 Hence, first four terms of AP are 10, 20, 30, 40 …… Ex 5.1, 2 Write first four terms of the A.P. when the first term a and the common difference d are given as follows (ii) a = −2, d = 0 First term = a = –2 Common difference = d = 0 Second term = First term + Common difference = –2 + 0 = –2 Third term = Second term + Common difference = –2 + 0 = –2 Fourth term = Third term + Common difference = –2 + 0 = –2 Hence , first four term of AP are – 2, –2, –2, – 2 Ex 5.1, 2 Write first four terms of the A.P. when the first term a and the common difference d are given as follows (iii) a = 4, d = −3 First term = a = 4 Common difference = –3 Second term = First term + Common difference = 4 + (–3) = 4 – 3 = 1 Third term = Second term + Common difference = 1 + (–3) = 1 – 3 = –2 Fourth term = third term + common difference = −2 + (–3) = –2 – 3 = –5 Hence, first 4 terms of AP are 4, 1, –2, –5 Ex 5.1, 2 Write first four terms of the A.P. when the first term a and the common difference d are given as follows (iv) a = − 1 d = 1/2 First term = a = –1 Common difference = d = 1/2 Second term = First term + common difference = – 1 + 1/2 = (−2 + 1)/2 = (−𝟏)/𝟐 Third term = Second term + common difference = (−1)/2 + 1/2 = 0 Fourth term = third term + common difference = 0 + 1/2 = (0 + 1)/2 = 𝟏/𝟐 Hence first four terms of AP are –1, (−𝟏)/𝟐 , 0, 𝟏/𝟐 Ex 5.1, 2 Write first four terms of the A.P. when the first term a and the common difference d are given as follows (v) a = −1.25, d = −0.25 First term = a = –1.25 Common difference = d = –0.25 Second term = first term + common difference = –1.25 + (–0.25) = –1.25 – 0.25 = –1.50 Third term = second term + common difference = –1.50 + (–0.25) = –1.50 – 0.25 = –1.75 Fourth term = third term + common difference = –1.75 + (–0.25) = –1.75 – 0.25 = –2.00 Hence first 4 terms of AP are –1.25, –1.50, –1.75, –2.00