Page 16 - PBD Plus Matematik T5 (EG)

Matematik Tingkatan 5 Bab 1 Ubahan
12. Selesaikan. TP 3
Solve.
Contoh
Diberi W berubah secara langsung dengan H dan (a) Diberi A berubah secara langsung dengan M
dan kuasa dua T. Jika A = 200 apabila M = 5 dan
punca kuasa tiga M. Jika W = 25 apabila H = 2 dan T = 4, hitung
M = 125, hitung Given A varies directly as M and the square of T. If A = 200
Given W varies directly as H and the cube root of M. If W = 25 when M = 5 and T = 4, calculate
when H = 2 and M = 125, calculate
(i) nilai W apabila H = 3 dan M = 64, (i) nilai A apabila M = 2 dan T = 3,

the value of A when M = 2 and T = 3,
the value of W when H = 3 and M = 64,
(ii) nilai M apabila W = 3 dan H = 0.4. (ii) nilai T apabila A = 375 dan M = 1.5.
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the value of T when A = 375 and M = 1.5.
the value of M when W = 3 and H = 0.4.
2
3

W ∝ H√M A ∝ MT 2
3
W = kH√M A = kMT 2

3
25 = k(2)√125 200 = k(5)(4)

k = 2.5 k = 2.5
3
3

(i) W = 2.5H√M (ii) W = 2.5H√M (i) A = 2.5MT (ii) A = 2.5MT
2
2
3
3
W = 2.5(3)√64 3 = 2.5(0.4)√M A = 2.5(2)(3) 375 = 2.5(1.5)T 2

2
2
W = 30 3 √M = 3 = 45 T = 100
M = 27 T = ±10
13. Selesaikan. TP 4
Solve.
Contoh
Jadual di bawah menunjukkan perubahan tiga kuantiti. Diberi A berubah secara langsung dengan B dan
punca kuasa dua C. Hitung nilai p dan nilai q.
The table shows the changes in three quantities. Given A varies directly as B and the square root of C. Calculate the value of p
and of q.
A 20 12.5 q
B 4 2 6
C p 25 36
A ∝ B√C A = 1.25B√C A = 1.25B√C
A = kB√C 20 = 1.25(4)√p q = 1.25(6)√36
12.5 = k(2)√25 √p = 4 q = 45
k = 1.25 p = 16

(a) Jadual di bawah menunjukkan perubahan tiga kuantiti. Diberi P berubah secara langsung dengan Q
dan kuasa dua R. Hitung nilai p dan nilai q.
The table shows the changes in three quantities. Given P varies directly as Q and the square of R. Calculate the value of p and of q.

P 20 15 640
Q 5 p 2.5
R 0.4 2.0 q

P ∝ QR P = 25QR P = 25QR
2
2
2
P = kQR 15 = 25p(2.0) 640 = 25(2.5)q
2
2
2
20 = k(5)(0.4) p = 0.15 q = 10.24
2
2
k = 25 q = ±3.2
Cuba jawab Praktis SPM 1, K1: S7
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