Intro
Ab tak humne integers ko add aur subtract karna sikha.
Ab multiplication aata hai.
Yahan sabse bada confusion hota hai: sign ka kya hoga?
Answer positive aayega ya negative?
Aaj hum sirf multiplication ke sign rules sikhenge.
Bilkul step-by-step, bina tension.
Concept Explanation (What, Why, How)
Simple explanation
Integers multiply karte waqt 2 cheezein hoti hain:
- Numbers ka size multiply hota hai (absolute values)
- Sign rule se decide hota hai
Sign rules:
- +×+=+
- +×−=−
- −×+=−
- −×−=+
Detailed explanation
What (Kya?)
Aapko questions milenge:
- 3×4
- 3×(−4)
- (−3)×4
- (−3)×(−4)
Why (Kyun?)
Sign ka logic direction jaisa hai:
- Positive = forward/gain
- Negative = backward/loss
Jab ek negative aata hai, direction change hoti hai.
Aur jab do negative aate hain, direction do baar change hoti hai, to wapas positive.
How (Kaise?)
Step-by-step method:
- Absolute values multiply karo (sign ignore)
- Sign count karo:
- Negative signs odd (1,3,5…) → answer negative
- Negative signs even (0,2,4…) → answer positive
Ye quick trick exam mein fast hai.
More
Socho “minus” ek switch hai.
Ek switch press kiya to direction ulta.
Do switch press kiye to direction wapas seedhi.
- Ek minus → answer negative
- Do minus → answer positive
Aur number ka size?
Woh normal multiplication se aata hai.
Example:(−2)×(−3)
Size: 2×3=6
Minus minus: plus
Answer: +6
Examples
Example 1
3 × (-4) = -12
Example 2
(-6) × 5 = -30
Example 3
(-7) × (-2) = 14
Real life usage
Socho har din ₹50 ka loss ho raha hai.
Loss ko hum negative maan lete hain: -50.
Agar ye loss 3 din tak hua:
−50×3=−150
Matlab total loss ₹150.
Ab socho “loss ko remove karna” (negative of negative) wali feeling:
Kabhi-kabhi math mein do negatives milkar positive banate hain—jaise wrong direction ko do baar flip karo to right direction.
Try It Yourself
Sign rule laga kar solve karo:
- 4×(−3)
- (−8)×2
- (−5)×(−6)
- (−2)×(−3)×4
Summary
- Multiply magnitude (absolute values) normally
- Sign rules:
- Same signs → positive
- Different signs → negative
- Negative signs odd → negative, even → positive
Next
Next: Dividing Integers – sign rules same as multiplication
